What is the definition of a variable cost? Multiple Choice

The total cost (materials, labor, and overhead) is divided by the number of units of output.

A cost that varies with the cost driver, but in discrete steps within the relevant range; is also called a semi-fixed cost.

A cost that changes in total in response to changes in one or more cost drivers.

A cost that, within the relevant range, includes both variable and fixed cost components.

The portion of the total cost that, within the relevant range, does not change with a change in the quantity of a designated cost driver.