What does a company's customer service department do?

A. Receive payments from customers and handle the company's money

B. Promote the company to new groups of potential customers

C. Interact with customers after they have purchased the product

D. Handle employee-related procedures

I believe the answer is: C. Interact with customers after they have purchased the product.

The interaction that made by the customer service usually revolves around questions about how to use the product and listening to consumers' complaint if they're experiencing problems when they use the product.