A small group of islanders leave "island A" and travel to "island B." After several generations on island B, a researcher finds that a large percentage of the population is left-handed. Left-handedness is a relatively rare trait on island A. A genetic event that explains this is
A. A population bottleneck
B. Genetic load
C. A founder effect
D. Natural selection

C. A founder effect

Explanation:

When a few individuals from a population migrate to some other region and establish a new population, the allele frequencies of the new population might not be the same as that of the original population. This is called the founder effect. Founder effect allows some rare genetic traits present in a low proportion in the original population to become abundant in the new population. Therefore, the increased proportion of the left-handedness in the population on island B represents the founder effect.