The Main Reason That Starbucks Was Able to Have the Main

The main reason that Starbucks was able to have the main share of coffeehouses in the world is just two decades is that they:

A) were the only coffeehouse to offer premium coffee during extended hours.
B) used tangible resources to provide their product.
C) capitalized on the economic climate at the most opportune time.
D) continually expanded their stores at the expense of customer service.
E) successfully applied their knowledge and skills to better serve customers.