Before using any chemicals, which of the following must not be present in the area?

The correct response highlights the importance of keeping food items safe from contamination during the use of chemicals. When chemicals are used in a food preparation area, the presence of food can lead to potential contamination, which poses a serious health risk. It is essential to ensure that food items are removed from the vicinity to prevent any accidental chemical exposure, as this can compromise food safety and lead to the risk of foodborne illnesses.

Customers, equipment, and cleaning supplies can also play roles in maintaining a safe environment, but the immediate focus should be on protecting food from harmful substances. This is in line with food safety protocols that prioritize the integrity and safety of food items above all else, thus ensuring that the food served to customers remains safe to consume.