PT 61 S2 Q15

Often a type of organ or body structure is the onlyphysically feasible ... ...

Which one of the following most logically completes the last sentence of the passage?
(A) will often live in the same environment as other species quite different from themselves
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Complete Section: LR-A, Oct. '10 LSAT (PT 61 Sec. 2)