The Best Practices Adopted by the Champions Included in This

The best practices adopted by the champions included in this study can be broadly categorized into three areas. Which of the following was not one of the three areas?

A) Those of which focus on providing high quality customer service
B) Those that stress providing a high-quality F&B product
C) Those that emphasize the elements of restaurant concept and design
D) Those which focus primarily on controlling costs and generating additional revenue