Answer:
Controllable costs.
Step-by-step explanation:
Controllable costs are those that tend to be altered in the short term. The decision to incur these cost usually resides with one person. If the person making the decision is the manager, then the best way to assess the manager's cost performance is by evaluating controllable cost.
When the decision to incur a cost rests with more than one person then the cost is not controllable by the individual, and will not be a good yardstick to measure the manager's cost performance.