Which of the Following Scenarios Would Most Likely Lead to Adaptive

Multiple Choice

Which of the following scenarios would most likely lead to adaptive radiation in a species?

A) An isolated patch of rainforest in the country of Belize is cut down. This changes the abiotic conditions that the birds living in this habitat will be facing if they are to survive.
B) A mutation occurred in a population of howler monkeys that increases their fitness.
C) Females start mating more frequently with the males in the group that sing differently than the rest of the group.
D) Adaptive radiation doesn't occur in populations since species are fixed.