Question

a new species of oyster has established a home in the gulf of mexico on the mississippi coast. only the oysters with the hardest shells thrive in the new environment. what type of selection is occurring? no selection disruptive selection stabilizing selection directional selection

Explanation:

Directional selection favors individuals at one extreme of a trait. Here, oysters with the hardest shells are the ones that thrive, shifting the population towards having harder - shelled individuals. Disruptive selection favors both extremes, stabilizing selection favors the intermediate, and clearly there is selection occurring as only certain oysters survive.

Answer:

D. Directional selection