PT 22, section 4, Q22 (dinosaur expert)

[icobes]

Why is the answer (D) and not (C)? If we deny (C) and say that the knowledge of the fossils is not complete, then that opens up the possibility that an older dromeosaur fossil has not yet been found, which would completely discredit the argument that the paleontologist's claim was false. I don't see how (D) is relevant at all to the stimulus.

Thanks for the help!

[JacobH]

You'll have to pick the one that the author most depends on.

For C, does the entirety of knowledge of dromeosaur and bird fossils have to be complete? Do we have to know everything? Not necessarily. This answer choice reached a little bit farther than D.

If we were to negate D such that the known fossils did not indicate the dates of origin of birds and dromeosaurs, then yes, there is a big reason to doubt the expert's claim, which is, as you stated, that there is a possibility that earlier dromeosaur fossils could be found.

If we assume D, then no earlier dromeosaur fossils will be found, then his claim can be made.