Suppose That Irina Is Prepared to Pay a Maximum of $2.40

Multiple Choice

Suppose that Irina is prepared to pay a maximum of $2.40 for her first glass of cranberry juice,but for each subsequent glass she is only prepared to pay 20 cents less than the previous one.
-What is the correct formula for MCS (marginal consumer surplus) ?

A) $MU-price.
B) Price-$MU.
C) $TU-price.
D) $\Delta$ TU/price.
E) $\Delta$ TU/ $\Delta$ quantity.