[QA] It would have been better if he had told us his new address.

Question:

It would have been better if he had told us his new address.

• A.
  He might have told us his new address.
• B.
  He should have told us his new address.
• C.
  He must have told us his new address.
• D.
  It doesn’t matter that he didn’t tell us his new address.