How does sir gawain show courage?

In the version of king Arhtur I read sir gawian does none of these, he chops off the green knights head and the green knight somehow survives and says to come to his castle and he will give what was given or something like that. So he shows courage by going to get his head chopped off. In the end the green knight decides not to ( chop gawains head off) because of his show of bravery. I personly would choose b because that sounds like a reasonable answer