Scientists Found That Different Beak Shapes Lead to Different Mating

Scientists found that different beak shapes lead to different mating songs in Darwin's finches. This result best supports which hypothesis?

A) Darwin's finches are not different species according to the Biological Species Concept.
B) Adaptation to different food sources indirectly led to behavioral isolation in Darwin's finches.
C) Behavioral isolation in Darwin's finches is unrelated to beak shape.
D) Adaptation to different food sources likely occurred after reproductive isolation in Darwin's finches.