The Observation That a Whale's Front Flippers Have the Same

Multiple Choice

The observation that a whale's front flippers have the same bone structure as all mammalian forelimbs suggests that

A) all mammals descended from a common ancestor.
B) whales once walked on land.
C) whales show remarkable diversity.
D) land mammals originally came from the sea.
E) there must have been land and aquatic ancestors that coevolved.