在一些山区的溪流里能见到一些大蝌蚪没能正常完成变态发育,其原

在一些山区的溪流里能见到一些大蝌蚪没能正常完成变态发育,其原因是体内缺乏(   

A.性激素        B.生长激素      C.生长抑制素    D.甲状腺激素

答案

D

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