He was very_____to go，but he had no choice.
C
reluctant“不愿的，勉强的”：“他非常不愿意去，但他别无选择”，所以，reluctant用的本句合适。hesitant“踌躇的，犹豫的”;ready“准备好的”;willing“愿意的”。
Thedriverpulled_____atthetrafficlights.
It‘s_____mypowertomakefinaldecisiononthematter.
Icanspeak_____German.
Copernicusmaintainedthattheearth_____roundthesun.
He‘sworkinghard_____.