Mapping of the ocean floor

Correct answer: B. Bathymetry

Explanation: Bathymetry is the scientific measurement and mapping of the depth and shape of the ocean floor. It is similar to topographic mapping on land, but it focuses on underwater relief. Bathymetric information can show trenches, ridges, plains, seamounts, and changes in depth. This makes the term directly connected with maps of ocean-floor features. The word does not refer to weather, soil, or population.

Among the options, bathymetry is the only discipline concerned with underwater depth and relief, so option B is correct. Climatology studies climate and long-term atmospheric patterns. Pedology studies soil, while demography studies human population. Since the question asks for scientific mapping of ocean depths and features, the definition of bathymetry matches exactly.

Correct answer: A. Because sound goes to the ocean floor and returns

Explanation: The sound covers a two-way path so one-way distance is the depth. Exam tip: remember (d=\frac{vt}{2}).

Correct answer: C. Steep slope

Explanation: Closely spaced isobaths show rapid depth change. Exam tip: understand them like contour line spacing.

Correct answer: D. It is linked with fish and mineral resources

Explanation: The continental shelf is the gently sloping, shallow part of the seabed that continues outward from a continent before the sea floor drops more steeply. Because it is shallow and receives sunlight and nutrients, it supports productive marine life and important fishing grounds. Its sediments and geological setting can also contain valuable resources such as petroleum and natural gas. These combined biological and mineral resources make the shelf economically important.

Option D is correct because it connects the shelf with fisheries and mineral resources. Option A is wrong: the shelf is generally shallow, not the deepest part. Option B describes only one possible marine process and does not explain the shelf’s economic value. Option C refers to deep ocean trenches, which are different from broad, shallow continental shelves. Thus the supplied answer and explanation are accurate.

Correct answer: B. Because it connects the shelf with the deep ocean floor

Explanation: The continental slope descends from the shallow shelf to the deep sea. Exam tip: remember the order shelf slope rise.

Correct answer: D. Sediments cover uneven parts

Explanation: Sediments deposited in the deep sea reduce unevenness. Exam tip: link sediments with abyssal plains.

Correct answer: C. They are linked with creation of new ocean floor

Explanation: Mid-oceanic ridges are major zones of sea-floor spreading. Exam tip: connect ridges with divergent boundaries.

Correct answer: A. Subduction

Explanation: Trenches often form where one plate sinks beneath another. Exam tip: link trenches with convergent plate boundaries.

Correct answer: C. By measuring tiny sea-surface height variations

Explanation: Large undersea highs can cause slight sea-surface changes through gravity. Exam tip: treat this as an indirect technique.

Correct answer: A. It surveys a wider swath of sea floor at once

Explanation: Multibeam sonar records depths over a wider area using many sound beams. Exam tip: link it with detailed and faster mapping.

Correct answer: B. Depth and bottom form of water bodies

Explanation: Hydrographic survey gives depth and bottom information of seas and water bodies. Exam tip: connect it with navigation charts.

Correct answer: C. Deposition of sediments at the base of the slope

Explanation: The continental rise forms from sediments deposited below the slope. Exam tip: place it between slope and abyssal plain.

Correct answer: A. Valley-like erosion and sediment transport on the sea floor

Explanation: Submarine canyons are submerged valleys and may act as sediment pathways. Exam tip: connect them with slope and deep sea.

Correct answer: B. The sea-floor slope is steep there

Explanation: Dense isobaths show large depth change over a short distance. Exam tip: infer slope from line spacing.

Correct answer: A. Misinterpreting colours and symbols

Explanation: The map key explains the correct meaning of colours depths and symbols. Exam tip: read the key before any map.

Correct answer: B. It shows mid-oceanic ridges and related patterns

Explanation: Ridges and ocean-floor structure help understand plate spreading. Exam tip: connect mapping with evidence of plate tectonics.

Correct answer: C. Risk of ship grounding or collision

Explanation: Wrong depth can make a ship hit shallow areas or obstacles. Exam tip: link accurate measurement with safety.

Correct answer: C. Because shallow water and nutrients may be available here

Explanation: Shallow water with light and nutrients is favourable for many organisms. Exam tip: link shelves with fisheries.

Correct answer: B. It helps understand undersea seismic zones and slopes

Explanation: Ocean-floor structure and seismic zones are linked with tsunami risk. Exam tip: remember the trench earthquake tsunami relation.

Correct answer: A. To take cables through safe slopes and low-risk routes

Explanation: Depth slope and obstacles affect cable routes. Exam tip: connect it with communication infrastructure.

Correct answer: A. Greater influence of coastal sediments and human activities

Explanation: The shelf is near the coast so sediments and human use may be greater. Exam tip: remember coastal influences.

Correct answer: B. Ocean-floor cross profile

Explanation: Depth data can show the floor shape from coast to deep sea. Exam tip: treat profiles as tools to understand relief.

Correct answer: A. It gives clues about plate boundaries and volcanic activity

Explanation: Ridges trenches and seamounts can be linked with internal dynamics. Exam tip: connect marine features with tectonics.

Correct answer: A. Oceanic ridge

Explanation: Direct answer: A, an oceanic ridge. A bathymetric map shows the shape and depth of the ocean floor, just as a relief map shows land heights. A long elevated belt on the seafloor is called an oceanic ridge. It is an underwater mountain chain or raised zone, often extending for great distances. A is correct. B, marine desert, is not a standard landform meaning a long raised belt. C, land plain, is a feature on land and does not describe an underwater elevation. D, pressure belt, is an atmospheric zone based on air pressure, not a seafloor shape. Read the map clue carefully: long and raised means ridge; deep and elongated may suggest a trench. Memory cue: ridge rises; trench sinks.

Correct answer: A. Because they can be possible submerged obstacles

Explanation: Seamounts may remain below the surface and still pose route risks. Exam tip: remember submerged obstacles.