The cost of supplies used by a specific department is classified as which type of expense?

The cost of supplies used by a specific department is classified as a direct expense because it can be directly traced to that department's operations. Direct expenses are those that are specifically incurred for a particular department or function, and thus their costs can be attributed directly to the revenue generated by that department.

For example, if a marketing department uses paper and printing supplies for promotional materials, these supplies are a direct expense because they are essential for the department's activities. This direct relationship between the expense and the department's operations helps in accurately analyzing the profitability and financial health of that specific segment of the business.

In contrast, the other types of expenses—indirect, fixed, and variable—do not have the same direct correlation to a specific department’s operations or are not as easily attributable to revenue generation in that area. Indirect expenses are more general and benefit multiple departments, fixed expenses do not fluctuate with production levels, and variable expenses change in direct proportion to production volumes.