Which of the following statements would be least acceptable to most zoologists?
A) The extant lancelets are contemporaries, not ancestors, of vertebrates.
B) The first fossils resembling lancelets appeared in the fossil record around 530 million years ago.
C) Recent work in molecular systematics supports the hypothesis that lancelets are the most recent common ancestor of all vertebrates.
D) The extant lancelets are the immediate ancestors of the fishes.
E) Lancelets display the same method of swimming as do fishes.
Answer: D
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