Individual birds have different colored feathers. Island finches have a large number of offspring. Individual birds of an island finch species have many differences. Island finches share a common ancestry with mainland finch species.
Charles Darwin made a number of observations and inferences during his travels. He studied island finches during a long period of time. Which statement is an inference?

Options:
- Individual birds have different colored feathers.
- Island finches have a large number of offspring.
- Individual birds of an island finch species have many differences.
- Island finches share a common ancestry with mainland finch species.

Island finches share a common ancestry with mainland finch species.