Why Do Skates and Rays Have Flattened Bodies,while Sharks Are

Question

Why do skates and rays have flattened bodies,while sharks are torpedo shaped?
A)Sharks are more closely related to the tubelike lampreys than skates and rays are.
B)Skates and rays need enlarged pectoral fins to help them stay level in turbulent water, while sharks do not.
C)Skates and rays exchange gases across their skin and thus require a high surface-area-to-volume ratio, while sharks use gills to respire.
D)Sharks are streamlined for active swimming off the bottom, while skates move about mostly on the ocean bed.

Accepted Answer

Skates and rays spend most of their time on or near the ocean floor, so their flattened bodies allow them to blend in with the sand and rocks while still remaining visible to potential predators. Sharks, on the other hand, are active swimmers that move through the water column, so their streamlined torpedo shape helps them reduce drag and move more efficiently through the water.