Population Growth

Correct answer: B. Negative population growth occurs when the number of people added to a population is smaller than the number removed. Additions include births and immigration; reductions include deaths and emigration. Thus, if deaths plus people leaving are greater than births plus people entering, the total population falls. A is wrong because high births and immigration add people and normally support positive growth. C is wrong because births exceeding deaths create positive natural increase, unless a very large out-migration changes the total. D is wrong because immigration adds residents. The complete idea is not to look at one factor alone but to compare all additions with all reductions. Memory cue: additions − reductions; if the result is below zero, growth is negative.

Correct answer: A. Population explosion is a figurative term for very rapid and sustained growth in the number of people. It does not mean a literal blast. Such rapid growth can increase pressure on food, water, land, housing, schools, health services, and jobs, although the exact effects depend on planning and resources. A is correct because it includes both important ideas: high speed and continuation over time. B is wrong because slow growth is not an explosion. C is wrong because a stable population is not increasing quickly. D is wrong because a decline means the total is falling. The term should describe a strong trend over time, not just one unusually large annual change. Memory cue: “explosion” in this topic means fast, sustained increase, not a physical explosion.

Correct answer: A. Age structure shows how a population is divided into age groups, such as children, working-age people, and older people. A population with many young people may have more people entering reproductive ages in the future. If birth rates remain significant, this can influence future births and population growth. This does not mean every young person will have children or that growth is guaranteed; age structure is one factor among several. B is wrong because age structure describes people, not rainfall. C is wrong because the age distribution can influence the number of people likely to form families and have children. D is wrong because age structure does not change the physical area of a place. Memory cue: age structure helps us think about the population’s future composition and growth.

Correct answer: A. Infant mortality rate is the proportion or rate of infants who die during infancy. When it falls, more babies survive than before, so the number of surviving children can increase. This can influence population growth, especially when the birth rate remains high. The exact long-term effect also depends on future birth rates, general mortality, and migration; therefore the option correctly says growth “may be affected,” not that a particular increase is guaranteed. B is wrong because fewer infant deaths do not stop births. C is wrong because mortality remains an important population component even when infant mortality falls. D is wrong because infant survival does not necessarily make migration decrease. Memory cue: lower infant mortality means more infants survive; it does not mean fewer babies are born.

Direct answer: Option A is correct. A growth rate tells us the speed of change, while total population tells us the actual number of people. A declining rate can still be positive. For example, a population may grow by 3% in one period and 2% in the next; it is still increasing, but more slowly. Option B is wrong because the population declines only when the relevant net change becomes negative, not merely because the rate has fallen. Option C is wrong because an increasing population can include births, deaths and migration; a lower rate does not mean births are zero. Option D is also unsupported: a falling rate does not prove that death rate is always higher. Memory cue: falling growth rate means slower growth, not automatically negative growth.

Direct answer: Option A is correct. Population planning uses present data and reasonable projections to estimate how many people may need services in the future. A growing population may require additional schools, teachers, hospitals, health workers, homes, transport, water supply, sanitation, food and employment opportunities. Estimation helps authorities prepare resources instead of reacting only after shortages appear. The exact future cannot be known with certainty, so projections are estimates based on assumptions about births, deaths and migration. Option B is false because population size and age structure strongly affect service demand. Option C is unrelated: population growth does not create rivers. Option D is also unrelated and does not describe planning. Memory cue: population projections turn expected numbers into plans for people’s needs.

Correct answer: A, net migration. Population change is affected by births, deaths and migration. Net migration means the number of people entering an area minus the number leaving it. Here, the birth rate is low, so births are not the main reason for the increase. However, high immigration means many people are entering the area, which can raise its total population. B is incorrect because a higher death rate generally reduces population. C changes the size of land, not the number of people. D describes rainfall, not a direct component of population change. Memory cue: people entering minus people leaving is net migration; positive net migration can increase population even when births are few.

Correct answer: A. Food security means that people can obtain sufficient, safe and nutritious food. Better food availability can improve nutrition, physical strength and general health, and it may reduce deaths caused by hunger or weakness. If fewer people die while births continue, the population may increase more quickly; this is why the effect on growth is indirect. B is wrong because food supply cannot double the geographical area. C is wrong because food security does not make births zero. D is wrong because people can still migrate when food is secure. Memory cue: food security mainly affects survival and health first; its population effect follows through the death rate.

Correct answer: A. Cities need housing, water, sanitation, transport, schools, hospitals and other services for their residents. If population grows or jobs attract more people faster than these facilities expand, demand becomes greater than supply. This can produce overcrowded housing, pressure on transport and shortages of basic services. B is incorrect because adequate services reduce pressure rather than increase it. C removes an important possible source of urban growth. D would not describe high population growth from births. Memory cue: urban pressure rises when people increase faster than infrastructure and services.

Correct answer: A. Every person needs resources such as water, food, energy, housing, transport and public services. When population grows, the number of users usually increases, so planners must estimate future demand and arrange supply fairly. Population growth does not determine only one resource; it affects several sectors together. B is wrong because population size and growth strongly influence demand. C confuses population information with a river measurement. D is unrelated: population growth does not prevent measurement of area. Memory cue: more people usually mean more future demand, so population data is essential for planning.

Correct answer: A. A higher average age at marriage can shorten the period during which a person may have children. Education may also improve awareness, decision-making and access to information about family planning. These factors can contribute to smaller families and a lower birth rate, so population growth may slow. This is a possible effect, not an automatic result in every place. B is impossible and unsupported. C is wrong because marriage age does not make deaths zero. D is wrong because migration depends on many economic and social factors and will not always increase. Memory cue: education and later marriage can reduce the number of childbearing years and may slow growth.

Correct answer: A. Population growth depends on the difference between additions and losses. If the death rate falls while the birth rate remains relatively high, many births are added and fewer people are lost, so natural increase can become large. B is wrong because without births, a fall in deaths alone does not create the same strong increase. C describes emigration, which reduces population. D describes a situation in which deaths exceed births, so population would decline naturally. Memory cue: falling deaths have the strongest growth effect when births are still high.

The direct answer is A: absolute growth can still be large. Growth rate is a percentage calculated in relation to the starting population, while absolute growth is the actual number of people added. For example, if a state has 10,000,000 people and grows by only 2%, the increase is 200,000 people. A smaller state with 100,000 people growing by 10% adds only 10,000 people. Therefore, a low rate on a very large base may produce a larger absolute increase than a high rate on a small base. Option B is wrong because a low rate is not the same as zero growth. Option C is wrong because absolute growth can be calculated by subtracting the earlier population from the later population. Option D is wrong because area alone does not determine population increase. Memory cue: “Rate is relative; absolute growth is the actual addition.”

The direct answer is A. A growth rate is a relative measure, whereas absolute growth is the actual number added. A small starting population can show a large percentage change without adding many people. For instance, if an area has 100 people and grows by 50%, it gains 50 people. If another area has 10,000 people and grows by 10%, it gains 1,000 people. The second area has the lower rate but the larger absolute increase. Option B is wrong because a finite population cannot automatically produce an infinite increase. Option C is wrong because the rate tells us how large the change is compared with the initial population. Option D is wrong because a positive growth rate indicates an increase, not a necessary decline. Memory cue: always ask, “Percentage of what base?”

The direct answer is A. Population growth describes how the number of people changes over time. The change is linked to births, deaths and migration. Studying it helps us understand the size and speed of change and helps planners think about schools, hospitals, housing, food, employment, transport and other services. Option B is wrong because population density means people per unit area, while growth means change in population over time; the two ideas are related but not identical. Option C is wrong because population can grow without any change in the area, through births or inward migration. Option D is wrong because population information is important for planning public services and resources. Memory cue: density asks “how crowded?”, while growth asks “how is the number changing?”

The direct answer is B, twenty percent. First find the absolute increase: current population minus previous population equals 36 lakh minus 30 lakh, or 6 lakh. Then compare this increase with the previous population, because the growth percentage is calculated on the original base. The formula is: growth percentage = (increase ÷ previous population) × 100. Therefore, (6 ÷ 30) × 100 = 20%. Option A is wrong because 6 is not one-tenth of 30; it is one-fifth. Option C is wrong because 6 is not 30% of 30. Option D mistakes the current population figure for the growth percentage. Memory cue: subtract first, then divide by the old population, not the new population.

Answer: A, the first country. Population growth rate is usually expressed as a percentage of the starting, or base, population. To compare absolute increase, first write the rule: absolute increase = base population × growth rate ÷ 100. If the rate is the same for both countries, the country with the larger base is multiplying that same percentage by a larger number. For example, at 10%, a population of 100 lakh increases by 10 lakh, while a population of 20 lakh increases by only 2 lakh. Thus the percentage rate is equal, but the number of people added is different. A is correct because the first country has the larger base. B is wrong because the smaller base gives a smaller addition at the same rate. C is wrong because a positive rate produces an increase, not zero. D is wrong because absolute increase depends directly on both the rate and the base. Memory cue: same percentage, bigger base means bigger numerical change.

Population growth is governed by both natural change and migration. In simplified form, population change equals births minus deaths plus net migration, where net migration is immigrants minus emigrants. A complete analysis must therefore consider all three processes rather than relying on one indicator. Option A is correct because it combines births, deaths and net migration. Option B ignores deaths and migration, so it cannot explain the full change. Area is used when calculating density but is not itself a component of population growth, making option C unsuitable. Language describes composition, not growth, so option D is also incorrect.

Answer: A. Population size and growth rate describe related but different ideas. If births are still greater than deaths, natural increase remains positive, so the total population continues to rise. However, if the difference between births and deaths becomes smaller than it was earlier, the rate of increase falls. For example, if births exceeded deaths by 10,000 people last year but by only 6,000 this year, the population is still increasing, but more slowly. A is correct because it combines positive growth with a declining speed of growth. B is wrong because deaths exceeding births create a negative natural change, unless migration offsets it; that condition alone does not show the stated situation. C is wrong because a zero population cannot continue increasing. D is wrong because people leaving usually reduce population. Memory cue: increasing means the change is positive; falling growth rate means the positive change is becoming smaller.

Answer: A, when the base population is very small. A growth rate is a percentage, while absolute increase is the actual number of people added. The relationship is absolute increase = base population × rate ÷ 100. Therefore, a high percentage applied to a small base may produce a smaller numerical increase than a lower percentage applied to a very large base. For instance, 50% of 2 lakh is 1 lakh, whereas 5% of 100 lakh is 5 lakh. The first rate is higher, but its absolute increase is lower. A is correct because it identifies the small base as the reason. B would generally produce a larger absolute increase, not a smaller one, when the rate is high. C is incorrect because growth must be measured over a stated period. D concerns area and does not by itself determine the number of people added. Memory cue: percentage tells proportion; absolute increase tells actual persons.

Answer: A, the population will remain approximately stable. Population change can be understood by balancing additions and subtractions. Births and in-migration add people to an area. Deaths and out-migration remove people. In simple form, net change = births + in-migration − deaths − out-migration. If the two adding components together equal the two subtracting components, net change is zero for that period. The total population therefore stays nearly the same, although people may still be being born, dying, arriving, or leaving. A is correct because it describes this balance. B is wrong because rapid growth requires additions to exceed removals. C is wrong because balance does not mean that everybody disappears; it means the total change is zero. D is wrong because density is a measure of people per unit area, not a result or substitute for population. Memory cue: equal additions and removals mean no net change.

Answer: A. Population density means the number of people living per unit of area, commonly written as population ÷ area. Population growth means a change in the number of people over time. If the population increases while the area remains constant, the numerator becomes larger and density increases. For example, 1,000 people in 10 square kilometres give a density of 100 people per square kilometre; if the population becomes 1,200 and the area stays 10 square kilometres, density becomes 120. A is correct because it states the required condition. B is wrong because population growth does not automatically change the physical area. C is wrong because death rate measures deaths, not people per unit area. D is wrong because growth is a change over time, whereas density is a population-area ratio. Memory cue: density asks “how many people per area?”; growth asks “how does the number change over time?”

Answer: A, the population growth rate may slow down. Natural population increase depends mainly on the relationship between births and deaths. Education and family planning can contribute to a gradual fall in the birth rate. If deaths do not rise at the same time, the difference between births and deaths may become smaller, so natural increase and the overall growth rate may slow. The population may still continue to grow for some time because the birth rate can remain higher than the death rate; a falling rate does not mean an immediate fall in population. A is correct because it describes a possible long-term effect without claiming certainty about every other factor. B is wrong because a declining birth rate does not instantly reduce the population to zero. C is wrong because education and family planning do not necessarily increase deaths. D is wrong because migration depends on many economic and social factors and does not automatically stop. Memory cue: lower births usually mean slower natural growth, not instant depopulation.

Answer: A. Natural increase is commonly understood as births minus deaths. If the death rate falls while the birth rate remains higher than, or sufficiently above, the death rate, fewer people are being subtracted from the population. The gap between births and deaths can therefore become larger, causing natural population growth to increase. Better health care, sanitation, nutrition, or disease control may contribute to lower mortality, but the exact result also depends on births and migration. A is correct because it includes the necessary condition that the birth rate is not very low. B is wrong because a falling death rate does not by itself make the population decline. C is wrong because death rates and birth rates are separate measures; one does not automatically become zero when the other falls. D is wrong because migration is a separate movement process and remains possible. Memory cue: in births minus deaths, a lower subtraction can leave a larger positive result.

Answer: A. Natural increase is the difference between births and deaths. Migration changes population through people entering or leaving an area. If a city has only a small positive difference between births and deaths but receives many people from other places, the increase caused by in-migration is larger than the increase caused by natural change. For example, a city might gain 2,000 people from births exceeding deaths but receive 20,000 migrants; migration is then the dominant contributor to growth. A is correct because it gives both required conditions: a small natural increase and high in-migration. B is wrong because without in-migration, migration cannot be the main source of growth. C is wrong because deaths exceeding births and no migration would normally produce decline. D is wrong because an uninhabited city has no resident population to grow in the stated way. Memory cue: natural increase is births minus deaths; migration is movement in or out.