External value chains involve which of the following activities?

External value chains are crucial in understanding how a business interacts with the world beyond its internal operations. These chains focus on the activities that directly relate to delivering value to customers, which includes customer service, marketing, distribution, and sales activities.

The correct choice, which pertains to the activities required to serve the customers, highlights the importance of customer-centric approaches in a business model. By prioritizing customer-related activities, businesses can ensure that they are meeting customer needs effectively, thereby enhancing customer satisfaction and loyalty.

In contrast, while internal auditing, developing business models, and purchasing processes play significant roles within a business, they pertain primarily to internal operations or strategy formulation rather than to the external value chain focused on customer service. Internal auditing primarily deals with compliance and efficiency assessments; developing business models is about the conceptualization of how a business intends to operate, and purchasing processes primarily reflect the sourcing of goods and services necessary for the business operations, rather than directly serving customers.