Final answer:
Food handlers must wash their hands before putting on gloves to ensure they do not transfer contaminants from their hands to the gloves and the food. The correct option is D.
Step-by-step explanation:
The correct answer to when a food handler's hands must be washed is d. Before putting on the gloves. Washing hands is crucial in preventing the spread of pathogens, particularly in a food handling environment.
According to best practices and recommendations from health authorities such as the CDC, handwashing should occur before, during, and after food handling.
The act of putting on gloves does not replace hand washing but instead is a supplementary barrier following proper hand hygiene.
Therefore, a food handler should always wash their hands before donning gloves to ensure that any contamination on the hands is not transferred to the gloves and then to the food being handled.
Washing hands thoroughly with soap and warm water for at least 20 seconds helps remove pathogens and ensures food safety. The correct option is D.