A new variety of Doritos is initially introduced in Ft. Worth, Texas; Columbia, South Carolina; Peoria, 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) multi-stage introduction
b) roll-out approach
c) test-market expansion
d) mass commercialization
e) trickle-down approach
Answer: b