During an operational audit of a chain of pizza delivery stores, an auditor determined that cold pizzas were causing customer dissatisfaction. A review of oven calibration records for the last six months revealed that adjustments were made on over 40 percent of the ovens. Based on this, the auditor:

A. Has enough evidence to conclude that improperly functioning ovens are the cause.

B. Needs to conduct further inquiries and reviews to determine the impact of the oven variations on the pizza temperature.

C. Has enough evidence to recommend the replacement of some of the ovens.
D. Must search for another cause since approximately 60 percent of the ovens did not require adjustment.