单项选择题
A.丙烷 B.乙烯 C.甲烷 D.乙烷
A.茶碱 B.麻黄素 C.吗啡碱 D.烟碱
A.(CH3)2NHB.(CH3)3NC.CH3NH2
A.(CH3)3NB.(CH3)2NCH2CH3C.CH3CH2NH2D.CH3NHCH2CH3
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