The correct answer is C. Keep existing customers and clients
Step-by-step explanation:
Customer service refers to the interaction with customers and support employees in a company provide to customer to guarantee he or she has the best experience when buying one product or service. A high-quality customer service implies providing complete information to customers, and helping them before, during, and even after their process in buying or looking for information in a company. The main purpose of this is that customers feel the support from employees, and are loyal to the company which means they will go back if they need the same service or products. Thus, the reason for quality customer service is "Keep existing customers and clients".