Which discovery could provide evidence against the theory of evolution?
a. primate and trilobite fossil in the same rock layer
b. human gene in birds, fish, insects and plants
c. a living whale with a basic hip bone structure
d. bat fossil with a different limb structure than modern bats

The correct answer is A. primate and trilobite fossil in the same rock layer

Explanation:

Trilobita is a class of marine arachnomorph arthropods that become extinct at the end of the Permian mass extinction about 250 million years ago. They were one of the most successful animals on earth and lived around 300 million years even more that dinosaur.

The fossil of early primates are nearly 55 million years old and the trilobite become extinct at least 250 year ago, therefore, this discovery provides evidence against the theory of evolution because the fossil of animals who extinct earlier should be found in lower region of soil than the fossil of animals who extinct later.  Therefore the correct answer is A.