Evidence That Sexual Selection May Play an Important Role in Speciation

Evidence that sexual selection may play an important role in speciation of Hawaiian swordtail crickets includes the fact that

A) genetic variation in male song and female preference created a reproductive barrier.
B) crickets only diverged ecologically when colonizing new islands.
C) genetic variation in male song was not accompanied by variation in female preference.
D) genetic variation in female preference did not influence gene flow between populations.