MajorNet Systems is a start-up company that makes connectors for high-speed Internet connections. The company has budgeted variable costs of $145 for each connector and fixed costs of $7,500 per month. MajorNet's static budget predicted production and sales of 100 connectors in August, but the company actually produced and sold only 84 connectors at a total cost of $21,000. MajorNet Systems's managers could set direct labor standards based on.

A) time-and-motion studies.
B) benchmarking.
C) continuous improvement.
D) All of the above.