I don't believe your dad is over fifty.He looks _____ forty.

I don't believe your dad is over fifty.He looks _____ forty.A.no older th
为什么不能用B呢?个人觉得,A和B都可以,只是表达的意思有点不同而已.用A的话表示,我不相信你爸已经50多岁了,他看起来只是40岁.用B的话,表示我不详细你爸爸已经50多岁了,他看起来最多就40岁.这两种理解不是都可以吗?
选项 A.no older than B.not older than
C.no older as D.none older as