Answer:
14 is the top one if im not mistaken and 15 is the third one if im not mistaken
Explanation:
Gallstones...................
It grows , as well as the internet does.
The answer is either A, the bottleneck effect or C, natural selection. The answer is most likely A because it is hinted that the predator fish was placed in the isolated stream. The predators eating the darters less than 5cm is natural selection though.