What do keeping environments clean, avoiding cross-contamination, cooking foods thoroughly, and chilling perishable foods
have in common?

they are all food safety regulations that are enforced by the u. s. government.
they people learn how to cook safely at home, but do not apply to restaurants,
they people practice safe food handling by reducing the risk of foodborne disease.
they do not have anything in common because they are separate principles of food safety.

The third option is your answer.

Explanation:

We keep environments like counter-tops clean to reduce risk of bacteria growing on them and then making their way into our system when we prepare and eat food. Cooking foods thoroughly does the same thing. Think salmonella; it's why there is no medium rare chicken, why you're not supposed to eat raw cookie dough, why you're not supposed to eat raw eggs, etc. etc. These bacteria cannot survived high temperatures (salmonella's is like 130 degrees F) and thus cannot reproduce and create an infection. Same can apply to putting things in the fridge. Some bacteria cannot produce as well or as fast in a cold environment, they would much rather prefer the warmth that is room temp. So by putting them in a chilling freezer or fridge, we can slow the rate at which they reproduce and cause the food to spoil, which then reduces the risk of someone ingesting the spoiled goods.

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