How he thinks would give a deeper insight into the characters thought process and how that characters life events have caused them to make the choices they do. Where as with A it's just a meer description. What we see from the outside and not actually part of his character. Where with answer B it's how other people perceive Charlie, how he presents himself and what others take away from that.
He wants to further his education, I know this because in the book it mentions him sneaking to the library now and then to study on poetry. In conclusion, this is why I'd give Devon this character trait.
