Final answer:
Feedback control is the essential function of periodically assessing a company's own planning, organizing, leading, and controlling efforts.
Step-by-step explanation:
The essential function of periodically assessing a company's own planning, organizing, leading, and controlling efforts is feedback control. Feedback control involves gathering information about actual performance, comparing it to desired performance, and taking corrective action if necessary.
For example, a company may set a goal to increase sales by 10% in a given quarter. Through feedback control, the company can regularly monitor its sales performance, compare it to the desired goal, and make adjustments to its strategies or tactics if it is not on track to reach the target.
Other options mentioned in the question, such as strategic audits, feedforward control, competitive audits, and internal audits, may also be important functions in organizational management, but they are not specifically focused on periodically assessing a company's own planning, organizing, leading, and controlling efforts like feedback control.