How might an author develop a round character in a story.

Iwas in a argument about a certain class grade with my teacher. it was a ‘a-’when i felt that i deserved a ‘a’. i showed him (my teacher) why i felt i derserved so. i questioned what i got wrong and showed him what i learned. i look back to that teacher with nothing but love and support because that’s the class that i actually learned the most. the moral of the story is to see where the other person is coming from and what they have done. also, when in a conflict, never attack the persons character. this will just make the argument end poorly.

The answer should be d if i’m wrong i’ll change my answer and fix it for you