With the ad auction, __________. When calculating Ad Rank, we look at the search terms the person has entered, the person's location at the time of the search, the type of device they're using (e.g., mobile or desktop), the time of the search, the nature of the search terms, other ads and search results that show on the page, and other user signals and attributes.
A) Ad placement is determined based on bids only
B) Ad placement is determined based on ad text alone
C) Ad placement is determined based on bids and ad quality
D) Ad placement is determined randomly