Which of the following is an example of variable cost?

A variable cost is a type of expense that changes in direct proportion to the level of production or sales. Raw materials are considered variable costs because their total cost will increase or decrease based on the quantity of goods produced. For instance, if a company manufactures more products, it will need to purchase more raw materials, leading to higher costs. Conversely, if production decreases, the cost of raw materials will also decline, reflecting their nature as a variable expense.

In contrast, the other options represent fixed costs. Rent remains constant regardless of production levels; insurance premiums typically do not fluctuate with the level of operations; and salaries are often fixed for employees, not varying with production unless structured otherwise (e.g., overtime pay). This distinction between variable and fixed costs is essential for businesses to manage their budgets and forecast profitability effectively.