单项选择题

下列哪对化合物可用于制备缩聚物?()

A.CH3(CH24COOH和NH2(CH26CH3
B.CH3(CH24COOH和NH2(CH26NH2
C.HOOC(CH24COOH和NH2(CH26CH3
D.HOOC(CH24COOH和NH2(CH26NH2