The main conflict is that Harry is now old enough to face voldemort for the first time. however harry does not know this so he assumes that this fight will be between him and snake but it will actually be between him and quirrel.
5 is opinion so you can basically say whatever you want
The answer is A, I hope this helps!
“That has a ring to it” “got the hang of it”
Answers:
1. Can’t be
2. Can’t have won
3. Must have been
4. Must be
5. Couldn’t have been
6. May have been
7. Ought to have left
8. Can’t be
9. Could turn out
10. Must have left
11. Should have won
12. Should be