【单选题】

You are trying to determine what cost and schedule trade-off will be most appropriate for your project. You have the option to select either a more experienced person at $120 per hour who can do the task in 45 days or a less experienced person at $80 per hour who can do the same task in 65 days.

A、tool you can use to facilitate making the decision is ______ .
A、cost of quality
B．cause-and-effect diagram
C．design of experiments
D．network diagrams