what role does differential reproduction play in natural selection?

a) some organisms have different reproductive success due to nongenetic traits.
b) some organisms have traits that them reach reproductive age.
c) different methods of reproduction result in some organisms being genetically altered.
d) reproduction varies among organisms due to pathogenic factors.

the answer is not a or d based on other posts. (or maybe the other posts were wrong? ) does anyone know?

Crinoids, also known as sea lilies, appear to be sea plants but are not plants at all. crinoids are an echinoderm species which uses anchoring structures called holdfasts to attach themselves to the sea floor. crinoids were most abundant in pennsylvania during the mississippian period, which ranged from 375 to 320 million years ago. fossils of the crinoids shows that during most of this time pennsylvania was that provided favorable conditions for crinoid growth. a) glacial terrain b) a dry and sandy plain c) mostly mountain ranges d) covered by warm, shallow seas