Which Statement About the Studies by Dybdahl and Lively on Snails

Which statement about the studies by Dybdahl and Lively on snails and their parasites is false?

A) The trematode preferentially infects snails with rare genotypes.
B) Parasites evolve more quickly in response to snails than snails evolve to parasites.
C) The trematode worm castrates males and sterilizes females.
D) The snail genotype that was most abundant at one point often changed from year to year.