What is the most basic exam point in the population growth topic?

Correct answer: Understanding change in population over time

The correct answer is A: understanding change in population over time. Population growth means the increase or decrease in the number of people during a period. To understand it, first identify the population at an earlier time, the population at a later time, and the length of the period between them. Births, deaths, immigration, and emigration can produce this change. Option A is correct because it gives the central idea from which calculations and further topics develop. Option B is wrong because weather is a separate geographical subject and does not define population growth. Option C is wrong because mountains are physical features, not the meaning of population change. Option D is wrong because soil colour is unrelated to the basic definition. A useful memory cue is “people plus time plus change”: population growth always involves people, a time interval, and a change in number. Do not confuse population size, which is a number at one time, with population growth, which is the change across time.