Answer:
C.
Step-by-step explanation:
He's hanging his head, most likely and commonly seen as a sign of shame. He then proceeds to say (as I assume) that whatever the action was that he did, he did for someone, to help or protect them.
A. Is the second most reasonable answer in my opinion, as the fact that whatever the conversation was stuck with him for so long is a probable sign that there was some form of lingering regret or shame attached to it.