Kristie Currently Spends Her $1,000 a Week Income as Follows

Multiple Choice

Kristie currently spends her $1,000 a week income as follows: $500 on X,$300 on Y,and $200 on Z.Her mother then gives her a $100 bill and tells her to use it to buy more Z.Kristie actually takes the $100 her mother gave to her,adds $40 to the $200 she usually spends on Z,and buys $240 worth of Z.Did Kristie's mother's $100 go to buy only Z?

A) Yes,because Kristie used her mother's actual $100 bill to buy Z.
B) No,because if it had,Kristie would have bought $300 worth of Z.Some of Kristie's mother's money went for what Kristie had next on her list of desired purchases.
C) Yes,since Kristie bought $240 worth of Z,and the amount of money her mother gave her is less than $240.
D) There is not enough information to answer the question.