A species of butterfly lives in a warm climate. The butterflies feed on the nectar of tropical flowers. Birds eat the butterflies, and they prefer to eat the butterflies with brighter wings.

What would most likely cause this species to become extinct?

the correct answer is: b. pantala flavescens, because these organisms would have a high level of genetic variation due to sexual reproduction.  

because involves two organisms (parents) whose genetic material combines, sexual reproduction leads to genetic variation in new generations of offspring. the offspring is an unique organism, with new genome, more protected with the higher ability to adapted. this process is fundamental to evolution.