题目内容：

几个英语单选
1.--Do you mind if I open the window?
--＿＿,but I've caught a bad cold today.
A.No,not at all.B.Yes,of course not.
C.Yes,please.D.I'm sorry.
2.--Mom,can you buy me a new MP3 when you are on business?
--As long as you are admitted to a key middle school,you＿＿get one.
A.could B.shall C.would D.can
3.As soon as my manager returns,I'll tell him when＿＿and see him.
A.you will ring him B.will you ring him
C.you ring D.do you ring
4.She shares＿＿my troubles as well as ＿＿my joys.
A./,/ B.in,/ C./,in D.in,in
5.The beautiful autumn＿＿the wet summer.
A.made up of B.made of C.made from D.made up for
以上5题的答案依次是ABABD
麻烦解释下原因,最好是每个选项都解释下.