Which of the following customer related costs are NOT economically feasible to trace but are related to a customer?

A) the additional cost of selling one more unit to a new customer who has never done business with the firm before

B) the direct material costs of a product that a customer has purchased

C) the allocation of the cost of travel, lodgings, and meals that result from visiting customers at their locations

D) the shipping costs that result from shipping a package by Fed Ex to a customer when the technology allows a direct match of that cost to the direct material and direct labor costs of the product