Matt Has Decided to Purchase His Textbooks for the Semester

Matt has decided to purchase his textbooks for the semester. His options are to purchase the books online with next day delivery at a cost of $175, or to drive to campus tomorrow to buy the books at the university bookstore at a cost of $170. Last week he drove to campus to buy a concert ticket because they offered 25 percent off the regular price of $16. The benefit to Matt of buying his books at the university bookstore instead of online is:

A) $5
B) $9
C) $170
D) $175