1.We are suprised that you ___ so rudely
a.shoud have behaved
b behaved
c.should behave
d might behave
The given answear is A, why?
2._____ I were a young and beautiful girl again.
A if
B Would that
C Only if
D Provided
The given answear is B, why?
3.You should have put the milk in the icebox; I expect it ____ undrinkable by now
B has become
C had become
The given answear is C, why?but there is a "by now " at the end of the sentence, so my choice is B, which one is right?
thx

BTW
Xmas