Crabs are organisms that have five pairs of legs. In certain species of crabs, the fifth pair of legs has a flattened, paddle-like shape. Which of the statements below best explains how this adaptation has evolved?
A.Crabs were exposed to a toxin in the water.


B.Crabs with this adaptation have an advantage over other crabs to defend against predators in oyster beds.


C.Crabs needed this adaptation to dig into sand to find food so they developed the flattened paddle-like shape.


D.Crabs developed this adaptation because they needed to climb mangrove trees to hide themselves from predators.