Final answer:
Both Sprint and Verizon prioritize customer service as their market focus.
Step-by-step explanation:
Both Sprint and Verizon are pursuing customer service as their market focus. Customer service is the value they prioritize in order to attract and retain customers. They aim to provide excellent service to their users by offering reliable and efficient communication services.
Evidence of their focus on customer service can be seen in the improvements in technology that both companies have made, allowing for better-quality phone service, cheaper phone calls, and faster data transmission. Additionally, the spin-off technologies such as free Internet-based calling and video calling also demonstrate their commitment to providing valuable services to their customers.
Therefore, the correct answer is customer service (d) as the market focus on which both Sprint and Verizon place value.