In the real world of brand recognition and popularity, accounts for the fact that mediocre products and services often trump quality.
a. lower cost
b. perception
c. consumer preference
d. foolishness

Since they are talking about brand recognition and popularity, I would say C. Perceptions accounts for mediocre products trumping quality.  People go with the product they know or they think more people are using because it is perceived as a better product even though it may not be.