The budget allowed for a cost center for the most recent fiscal year was $800,000. The actual cost for the most recent fiscal year was $720,000. The manager responsible for the cost center did better than expected with controlling costs if:

a. the cost is a variable cost and actual production was 90% of budgeting production.

b. the cost is a variable cost and actual production was equal to budgeted production.

c. the cost is a variable cost and actual production was 80% of budgeted production.

d. none of the above