Which of the following is a characteristic of variable costs in construction?

Variable costs in construction are characterized by their tendency to fluctuate according to the volume of work performed. This means that as more work is completed, these costs will increase, and conversely, if the amount of work decreases, so will the variable costs. Examples of variable costs include materials, labor directly related to production, and utilities that are consumed based on the level of activity on a construction site.

In contrast to variable costs, fixed costs remain constant regardless of the level of work or activity. Therefore, options suggesting that variable costs remain the same or are independent of work performed do not accurately describe their nature. Additionally, stating that variable costs are primarily fixed costs directly contradicts the definition of variable costs, as fixed costs are those that do not change with the volume of work. Thus, option C correctly identifies that variable costs change in accordance with the quantity of work completed.