The correct answer is A. Scientists reintroducing crested toads into the wild.
Step-by-step explanation
Species Survival Plan is a conservation program promoted by conservationists and zoologists that specializes in those animals that are near extinct, endangered, or threatened. This program mainly aims to breed these species in captivity to ensure their future preservation and reintroduction to nature. According to the above, the effect that could be expected from the implementation of the Species Survival Plan in Puerto Rico with the crested toads would be the reintroduction of this species into the wild after being bred in captivity.