Question: 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: 
 A. Individual birds have different colored feathers.
 B. Island finches have a large number of offspring.
 C. Individual birds of an island finch species have many differences.
 D. Island finches share a common ancestry with mainland finch species.
Answer: D