What Hypothesis Did the Scientists Test

What hypothesis did the scientists test?

A) That the frequency of a male's flashes indicated how healthy he was
B) That a male's flashes may correlate with the number of sperm he produces
C) That females reject males who present them small spermatophores
D) That females cannot determine the size of a male's spermatophore before mating
E) That a male's flashes may correlate with the size of his spermatophore