In a Shallow Bay,a Population of Oysters Is the Food

Multiple Choice

In a shallow bay,a population of oysters is the food source for the local crabs.The lightest colored oysters blend with the color of the rocks and the darkest colored oysters are concealed in the shadows cast by the rocks.Oysters with an intermediate coloring are easily detected by the crabs and become a tasty meal for them.Over time,fewer and fewer oysters display the intermediate coloring while more oysters are either the lightest coloring or the darkest coloring.This is an example of

A) stabilizing selection.
B) directional selection.
C) disruptive selection.
D) genetic drift.