問題詳情
38. The distinction between sponges and other animal phyla is based mainly on the absence versus the presence of
(A) a body cavity.
(B) a complete digestive tract.
(C) a circulatory system.
(D) true tissues.
(E) mesoderm.
參考答案
答案：D
難度：適中0.411765
統計：A(4),B(3),C(0),D(7),E(0)