Morrison Plastics currently produces plastic plates and silverware. The company is considering expanding its product offerings to include plastic serving trays. All of the following are relevant costs to this project except:

a. A percentage of the current operating overhead.

b. Any change in the expected sales of plates and silverware gained from offering trays also.

c. The cost of additional utilities required to operate the serving tray production operation.

d. The additional plastic raw materials that would be required.