Imagine That in One Portion of Their Range, Black Widowbird

Multiple Choice

Imagine that in one portion of their range, black widowbird numbers are declining due to the introduction of a non-native snake that eats their eggs and nestlings. The last two remaining females in this population disperse to join a different population that is 50 km away, where they breed with new males. If these females produce only sterile offspring as the result of mating with males in the new population, what type of reproductive isolation does this represent?

A) post-mating barrier
B) pre-mating barrier
C) temporal barrier
D) behavioral barrier