Which One of the Following Is an Example of Activity-Based

Which one of the following is an example of activity-based costing?

A) monitoring the salaries of managers that do untimely quality control checks
B) keeping close track of shrinkage associated with thefts off the showroom floor
C) insuring that management is closely working with the local union on keeping labour costs in line
D) allocating the set up cost associated with getting a machine ready for a production run