I'm guessing the word that is italicized capacious because in this case it is synonymous with vast, meaning that he has a developed mind with broad views.
Answer:
A is the correct answer
Explanation:
Process of elimination: If we're looking for the characters feelings towards being in Washington Square Park on a sunny day, we'd have to look for any sign of emotion in the sentences. A is the only one that's correct because it's the only one that gives emotion instead of details.