Asked if he could come to the party that night, _____.

A．nobody said anything

B．they did not get an answer from him

C．nothing was said by him

D．John nodded his head and left the room

依据我国《收养法》第9条的规定，无配偶的男性收养女性的，收养人与被收养人的年龄应当相差( )。

A．15周岁

B．20周岁

C．30周岁

D．40周岁以上