The crucible: how is john proctor NOBLE?​

John, though at first hesitant, is able to admit to his past faults and confess in order to show Abigails lies. It shows the audience his bravery and courage, knowing if he involves himself he to will be accused. However, he is willing to risk this to put down the reputation of Abigail, and also dies so his friends won't have to die alone.

a and c are the right ones