Final answer:
The coffee grower is engaged in business-to-business marketing when selling coffee beans to Starbucks.
Step-by-step explanation:
The coffee grower selling its coffee beans to Starbucks is engaged in business-to-business marketing. This type of marketing involves the sale of goods or services from one business to another. In this case, the coffee grower is selling their coffee beans to Starbucks, which is a business that will then sell the coffee to consumers.