选A,不能选B.原因：定于从句的动词live 后有介词时,不能用that做关系代词,只能用which .也可以去掉介词,用副词where,比较一下：
This is the house where he once lived when he was a child.
This is the house in which he once lived when he was a child.
This is the house which he once lived in when he was a child.
三句都行.因为that可以当关系副词用，因此我可以认为，这里的that=where，所以我认为可以选B。请问，为什么此处的that不能当作where用呢？注意： 凡是定语从句中“动词+介词”的话，不可以用that，记住。比较一下：This factory is the one which I once worked in.（用where就可去掉in） （work in the factory)The factory is the one that I once visited. (可用which）( visit the factoy)请看下面的句子：He is unlikely to find the place (that / where / inwhich) he lived forty years ago. 他不大可能找到他四十年前居住过的地方。据此，我的提问应可填where.不能用that， 其他两个都行。