Final answer:
The food would become unsafe due to cross-contamination.
Step-by-step explanation:
The food would become unsafe due to cross-contamination. Cross-contamination occurs when microbes, such as bacteria, are transferred from one food to another. In this case, if the food handler wearing gloves places a chicken breast on the grill and then places lettuce and tomato on a bun using the same gloves, any bacteria from the raw chicken could contaminate the lettuce and tomato, making them unsafe to eat.