The CPM in the business-to-business (B2B) context, what model/matrix best describes Turnbul and Zolkinuski?
a. The strategic importance of the customer, the difficulty of managing the relationship with the customer
b. Cintomer portfolio that importantly incorporated the idea of cost-to-serve into the evaluation of customer value
c. All of the above
d. 80% of sales are made to 20% of customers, 80/20 rule
e. 3-dimensional customer classification, cost to serve, net price and relationship value