if you can't control your manner of speaking well, then you said"你再说一遍", it might expresses that you are angry with what he just said.
in normal case, we will say"什(shen)么(me)？(what?)",or "不好意思,你刚才说啥(I'm sorry,what have you just said?)",
and the second answer is right too.
the third one is not always used, you can say 您可以再说一遍吗or您可以重新说一遍吗or麻烦您重新说一遍好吗or麻烦您再说一遍好吗...