Question

obviously, the military, aerospace and nuclear power facilities will test the calibration of their torque wrenches more often than a backyard mechanic, but generally speaking it is good practice to have mechanical torque wrenches calibrated _______________. only when problems are suspected quarterly monthly yearly

Explanation:

Mechanical torque wrenches don't need overly - frequent calibration like monthly or quarterly for general use. Waiting until problems are suspected is not good preventive maintenance. Yearly calibration is a reasonable general - practice frequency for maintaining accuracy without being overly burdensome.

Answer:

D. yearly