Which of the following is NOT a way food becomes unsafe?

Cooking food with excessive salt does not inherently make food unsafe. While high sodium levels can have health implications for certain individuals, such as those with specific health conditions, it does not create an environment that fosters foodborne illness or contamination.

In contrast, purchasing food from unsafe sources means that the food may come from a location that does not adhere to proper food safety standards, thus increasing the risk of contamination. Storing food at unsafe temperatures can promote the growth of pathogens, as bacteria thrive in temperatures between 41°F and 135°F. Using contaminated equipment poses a significant risk, as utensils, cutting boards, and surfaces that are not properly sanitized can transfer harmful microorganisms to food, leading to illness. Each of these options directly relates to causing foodborne illnesses and thus makes food unsafe for consumption.