Amazon Prime has one of the highest customer loyalty ratings in the entertainment industry with a signincant percentage of current video streaming subscribers continuing to renew their subscription with Amazon on a yearly $0$ month$-$to$-$month basis. In addition, many customers have cancelled their cable or satellite subscriptions and rely almost exclusively on streaming services such as Amazon Prime and Netflix for their entertainment. Amazon Prime video streaming is available as part of Amazon's $$99/$year Amazon Prime suite of offerings that includes free $2-$day shipping on many Amazon com orders. Customers can also choose to pay by the month for $$\frac{12\mathrm{.}99}{?}$ month. If a significant percentage of subscribers continue their service on an amnual basis, Amazon is able to build a stable revenue stream based on repeat purchasers. A quick snapshot of one customer revealed that the customer had subscribed to Prime for five years and generated over $$700$ in revenue to Amazon. Which of the following marketin terms best captures the importance of customer loyalty and its impact on Amazon?

a$)$ Customer retail calculation

b$)$ Customer lifetime value

C$)$ Customer profitability value

d$)$ Customer impact score

C$)$ Customer patronage value