Which word is an antonym of the underlined word in the paragraph?

Andrea glanced up from her handiwork to be sure no one was around. Making the scarf for her mother wasn't just a lark. It was hard, since it was the most difficult pattern she had ever attempted. It wouldn't be a surprise if anyone saw her. Suddenly she heard someone stirring and quickly stashed her work away.

A.
chore

B.
sport

C.
prank

D.
game
if you answer you get 50 points
srry lark is the under lined word:(