Cost behavior refers to the manner in which a cost a. is allocated to products b. is estimated c. changes as the related activity changes d. is used in setting selling prices

The correct answer is letter "C": changes as the related activity changes.

Explanation:

Cost behavior refers to the changes in total costs in front of changes due to certain events. Cost behavior is responsible for companies to classify costs in fixed costs - total costs do not vary even if there are changes in production, variable costs - total costs change when production changes, and mixed costs which is a combination of fixed and variables costs.

For a company, rent represents a fixed cost while raw materials represent a variable cost.