試題詳解

17. It has been observed that organisms on islands are different from, but closely related to, similar forms found on the nearest continent. This is taken as evidence that________.
(A) island forms are descended from mainland forms
(B) common environments are inhabited by the same organisms
(C)island forms and mainland forms have identical gene pools
(D) the island forms and mainland forms are converging
(E)None of the above.