The correct answer is A. Labor
Step-by-step explanation
Labor is the physical or mental effort that an employee makes to operate a machine with the best performance or perform some work. The work can be classified as Direct labor which refers to the work of the employee that is completely related to the elaboration of an object, that is, to the manipulation of the raw material and machinery; or as Indirect labor is related to the development of any work from administrative and managerial areas. So, the correct answer is A. Labor