What is the definition of customer service? A. The advice provided by a customer service rep over the phone.
B. The advice given between employees to help customers.
C. The assistance provided by a company to people who buy or use its products or services.
D. The assistance provided by a sales rep on the sales floor.

D, that would most likely be a common answer because why would costumer service be provided by a company instead of the sales rep?

The appropriate response is the Cluster sampling. Cluster sampling alludes to a sort of inspecting technique. With bunch examining, the specialist partitions the populace into discrete gatherings, called groups. At that point, a straightforward arbitrary example of groups is chosen from the populace.