Your answer should be B. He wants to help people, even if he does not know them.
It is shown through the fact that the speaker does not care whom he is helping by stating, "So I never saw them, couldn't recognize them, and couldn't describe them." This shows that he just wants to help people even without knowing whom it is.
Huck reacts by not being able to speak or breathe because he is so scared. I think he is starting to realize that life isn't forever and life can be quickly ended by other people, so you have to be careful with what kind of situations you put yourself in and who you surround yourself with.
