Use the Following to Answer Questions

Use the following to answer questions:
Calumet Inc is investigating its phone ordering costs and hoping to trace those costs to each of its three customer types, individuals, book stores and internet sales. Calumet uses in-house phone service for regular hours questions and orders and an outside source for weekend evening phone service.

-If Calumet believes the contribution margin on Internet customers is insufficient to cover the phone service costs and other related customer costs. An appropriate response would be:

A) Raise the cost of books sold on the Internet
B) "Charge" internet customers for phone service by replacing the toll free number shown on the web page with a toll call number
C) Use a separate phone numbers for Internet customers and increase the hold time for such customers to . reduce the overall phone service costs
D) All of the above