C is corrent. The requirement is to identify the type of costs that are assigned to goods for resale. C is corrent because product costs are assigned to such goods to move the costs to cost of sales when they are sold and to value inventory for financial statement purposes.
A is incorrect because opportunity cost is a benefit given up to pursue some course of action.
B is incorrect because a period cost is a cost that is expensed in the period in which it is incurred.
D is incorrect because a relevant cost is one that is relevant to a particular decision.
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