Refer to the Following Passage to Answer the Questions Below

Refer to the following passage to answer the questions below.
Allison works in the media department of a major advertising agency that has several national advertisers as clients. Her responsibilities include identifying specific media vehicles, such as TV programs, newspapers, magazines, or radio programs and stations for clients' advertising; negotiating the costs to advertise in them; and handling the details of billing and payment. Although one of the agency's major clients advertises primarily in magazines, the media plan calls for the use of newspaper advertising as well.
-What is Allison's job function?

A) media planning
B) rate negotiator
C) media buyer
D) account planner
E) account buyer