Which action should be taken to ensure cleanliness and safety when serving food?

Using tray jacks is an effective action to promote cleanliness and safety when serving food. Tray jacks help provide a stable and hygienic surface for transporting and serving food. They minimize the risk of spills and contamination, as food items can be placed on the tray jacks rather than held or carried directly in hand, which may not always be clean. By providing a designated space for food, tray jacks help prevent cross-contamination between different food items and between food and the serving personnel.

The other choices suggest practices that could lead to unsafe food handling. For example, avoiding the use of utensils jeopardizes sanitation and might contribute to the spread of bacteria. Directly delivering food to guests without washing hands increases the risk of transferring germs, while asking guests to serve themselves may lead to improper handling and touching of food items, compromising food safety standards.