Final answer:
Customer service in a firm's sales efforts refers to resolving issues and maintaining satisfaction after a customer has made a purchase. It is essential for building a positive reputation and encouraging repeat business.
Step-by-step explanation:
In the context of a firm's overall sales efforts, customer service is best described as the service that is required to solve a problem that a customer had with a previous purchase (option B). Customer service is a crucial element of the post-purchase experience and is focused on maintaining customer satisfaction, resolving issues, and ensuring repeat business. It is not simply about making a sale (A), it's about fostering a positive relationship and supporting the customer even after the transaction is complete. Exceptional customer service can lead to positive feedback, repeat business, and a good reputation, which are vital for a firm's success. While bundling (selling multiple products or services together at a better price) can be part of a strategy to attract customers, it is not the definition of customer service itself.