A New Variety of Cheetos Is Initially Introduced in Fort

A new variety of Cheetos is initially introduced in Fort Worth, Texas; Raleigh, North Carolina; Chicago, Illinois; and Spokane, Washington. After its initial success, Frito-Lay markets the Doritos in those entire states, then the adjacent states, and finally the entire country. Frito-Lay is using a ____ for its new variety of Doritos.

A) multistage introduction
B) rollout approach
C) test-market expansion
D) mass commercialization
E) trickle-down approach