Contrapositive and/or question

Aks_ZenMaster

Hi all,

Been stuck on one thing, if my stimulus says "If A then B and C", the contrapositive will be ~B or ~C then ~A. So can a must be true answer choice be "if ~B then ~A" or is that not valid? Also, can "if ~B, C then ~A" be a must be true answer choice or no?

Thank you!