Question

which of the following allows fish to survive high pressure?
fish have gills and not lungs
liquid water compresses less under pressure than gas
fish bodies are mostly composed of water
fish have air pockets in their bodies

Explanation:

• Option 1: Gills are for respiration, not related to withstanding pressure.
• Option 2: While water compresses less than gas, this alone doesn't explain fish survival without relating to their body composition.
• Option 3: Fish bodies are mostly water. Since liquid water is incompressible, having a body mostly of water means they can withstand high pressure as their body doesn't get compressed much.
• Option 4: Air pockets would compress under high pressure, harming the fish, so this is incorrect.

Answer:

• Fish bodies are mostly composed of water
• Liquid water compresses less under pressure than gas (Note: The most direct and correct primary reason is that fish bodies are mostly water. The fact that liquid water compresses less than gas supports why having a water - based body helps, but the key adaptation is the body composition. However, if multiple correct options are allowed, both the second and third options are related. But typically, the third option "Fish bodies are mostly composed of water" is the most direct answer as it links the fish's body to the property of water under pressure.)

(If we consider the most accurate single answer, it is "Fish bodies are mostly composed of water" as it is the characteristic of the fish's body that directly allows it to survive high pressure by leveraging the low compressibility of water. The statement about liquid water compressing less than gas is a general property that underlies why a water - based body is beneficial, but the fish's body composition is the key adaptation here.)