Answer:
Option-B
Step-by-step explanation:
Genetic drift refers to the change in the frequency of alleles (determines the trait of an organism) over some time due to chances.
Genetic drift is one of the mechanisms responsible for the evolution of an organism as the alleles could disappear from the small population randomly or new population could be founded.
In the given questions, a small population of anoles were transferred from the tropical rainforest to the new island and when observed after 5 years then the evolution could be observed as a result of the genetic drift. Genetic drift could be responsible as the anoles were chosen from the tropical forest which could be considered a chance or random event.
Thus, Option-B is the correct answer.