Which of the following is most likely an example of two organisms in the same species?

A.  A cabbage in Georgia and a cabbage in Missouri that mate and produce fertile offspring only in years of unusual weather patterns.

B.  Two fruit: flies on the same Hawaiian island with very different courtship dances.

C.  Two South American frogs that mate in different seasons.

D.  Two migratory birds that nest: on different: islands off the coast of England.

D is correct. Only D does not represent a type of isolation (geographic, seasonal, behavioral) which leads to speciation. The birds are migratory, and thus are not geographically isolated. This makes D the best answer choice.

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