The boy even imagined the old man was his enemy, who knew his intentions and had decided to frustrate them. he felt like entering and saying something insulting that would force the old man to leave, a rude word or phrase that would show him he had no right to sit there reading for an hour for so small a purchase.

which word from these sentences contributes most to the mood of restlessness and anger?

a.
frustrate

b.
purchase

c.
intentions

d.
imagined