Which of the Following Examples Does Not Illustrate Possible Routes

Which of the following examples does not illustrate possible routes to behavioral reproductive isolation?

A) Male wrens on either side of a mountain range sing slightly different songs.
B) In one species of moth, some males court females on daisies, while other males court females in-flight.
C) In one region of the Rocky Mountains, bighorn sheep breed in July, and in another region breeding takes place in September.
D) In a population of spiders, some females prefer males that bring nuptial gifts, while other females do not have that preference.
E) Some female fish in a pond prefer males that build large nests, while other females prefer males that build small nests.