Very small populations of island foxes are much more threatened by certain diseases than are very large populations of foxes. Which statement is the best explanation of this difference?

Large populations are made up of stronger individuals than small populations.

Small populations are more easily attacked by viruses.

Large populations can move away from disease sources.

Large populations are more likely to have have greater genetic variation

Explanation:

Following guidance from the Centers for Disease Control and Prevention ... Although the island fox is one of the smallest canids in the world, it is the largest ... The island fox is one third smaller than its mainland ancestor the gray fox. ... was able to reverse the certain extinction of an endangered population.

a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring.