一对表现正常的夫妇有一个正常男孩和一个患某种遗传病的女孩。如

一对表现正常的夫妇有一个正常男孩和一个患某种遗传病的女孩。如果该男孩与一个母亲为该病患者的正常女子结婚,生了一个正常的儿子,问这个儿子携带致病基因的几率为 (   )

A.11/18            B.5/9          C.4/9          D.3/5

 

答案

D

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