Which of the following is not considered a potentially hazardous food?

Cheddar cheese is considered a non-potentially hazardous food because it is a processed dairy product that undergoes fermentation and aging, which helps to inhibit the growth of harmful bacteria. While it must still be stored properly to maintain its quality and safety, it does not generally provide an environment conducive to rapid microbial growth like the other options mentioned.

In contrast, chicken, milk, and sliced tomatoes are all more susceptible to bacterial contamination and growth. Chicken is a raw protein that can harbor pathogens like Salmonella and Campylobacter. Milk can also support the growth of bacteria if not kept at proper temperatures. Sliced tomatoes, being fresh and moist, can become a medium for bacteria if not handled correctly. Therefore, cheddar cheese stands out as a less hazardous option in this context.