B is your answer, I believe
A)the crow flew to the south when the crow was tired
b)the crow stopped when he landed in a tree
c)the boy is small which he was playing outside
d)crow grabbed the ball of daylight when he flew away
the answer is
Ambifuos reference.
It is not clear that the <em><u>it </u></em>as a pronoun reference refers to the fact of singing higher or being different from others.
