PT 62 S2 Q12

   Paleontologist: Plesiosauromorphs were gigantic,long-necked ... ...

Which one of the following is an assumption on which the paleontologist's argument depends?
(A) Birds and reptiles share many physical features because they descend from common evolutionary ancestors.
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Complete Section: LR-A, Dec. '10 LSAT (PT 62 Sec. 2)