Shirley Promised Jill That She Would Give Her $50,000 If

Shirley promised Jill that she would give her $50,000 if she won the lottery.Shirley later won the lottery and gave Jill $50,000.Shirley later changed her mind and demanded the money back.What happened?

A) Shirley had to give the money to Jill because she promised it in certain terms and Jill was willing to accept.
B) Shirley did not have to give the money,but once she did,Jill did not have to return it.
C) Shirley had to give the money,but Jill had to return it when Shirley asked that she do so.
D) Shirley did not have to give Jill the money,and Jill had to return it.