Which one is best adapted to live in open water in the epipelagic zone, and why?

Fish A because of its elongated body and powerful tail

Fish B because of its flattened shape and eyes on the dorsal side

Fish C because of its streamlined shape and lack of pectoral fins

None of these because they are all sedentary

Answer: Fish A because of its elongated body and powerful tail.

Explanation: An elongated body gives the fish a streamlined or fusiform shape. This enables them to slide more esily through water, thus decreasing the energy expenditure of the fish for swimming. Powerfull tails also enables them to swim over long distances as well as bursts of speed. This speed capability is vital when the fish will either try to avoid a predator or, if it is a predator itself, catch its prey.