Plum Plumbing Supplies has three support departments (Quality Control, Training, Information System) and two operating departments (Consulting Maintenance). The department costs prior to support cost allocation, and the cost allocation basis for each support department, are summarised it the table below. Plum Plumbing Supplies uses the step-down method to allocate its support department costs. Which of the following is the correct order of allocating support department costs using the step-down method? a. Quality Control, then Training, then Information System. b. Training, then then Information System, then Quality Control c. Information system, then Quality Control, then Training d. Quality Control, then Information system, then Training e. Training, then Quality Control, then Information System