Conditions for the preservation of fossils are best fulfilled where?

Question

A. on river beds
B. on ocean floors
C. in the desert
D. on the floors of shallow seas

Answer 1

D. On the floors of shallow seas.
I have seen many fossils in marine environments and few fossils in desert environments. Of course, I have seen few desert environments (mostly Permian in age) so this may be the reason why, but I'll still hold to my answer.

Answer 2

c