25. Some 530-million-year-old Chinese fossils resemble lancelets but have a more elaborate brain and a brain case (cranium). These fossils may represent
(A) an early vertebrate.
(B) a non-tetrapod gnathostome.
(C) a primitive bony fish.
(D) a "missing link" between the urochordates and cephalochordates.
(E) the first chordate.
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統計: 尚無統計資料
統計: 尚無統計資料