C
因为母亲的红细胞能被儿子凝集,所以儿子不可能是A型或AB型,而父亲的能被母亲的凝集,说明父亲不能是A型,而如果父亲是AB型,则母亲的血细胞不会被父亲凝集,所以父亲不能是AB型,如果是O型,则父亲的红细胞不会被母亲和儿子凝集,所以父亲是B型,
而儿子不能是A和AB,如果是B型,则父亲的红细胞又不会被儿子凝集,所以儿子只能是O型,这样, 父,母亲儿子的血型为B A 和O型,A型和B型的父母有O型的儿子,则双方的基因中必有i等位基因.也就是C的选项.[详细]
How to protect the environment It's very impont for us to protect the environment good environment can make people feel happy and fit.To improve the environment means to improve our life. we should plant more trees and flowers ...[详细]