Cold temperatures affect the growth of microorganisms by:

Cold temperatures affect the growth of microorganisms primarily by inhibiting growth. Most microorganisms, including bacteria, thrive in warm environments, where they can rapidly multiply. When temperatures drop, enzymatic reactions that are crucial for their growth slow down significantly.

This decreased metabolic activity means that the reproduction and overall growth of these microorganisms are inhibited. While some microbes, such as psychrophiles, can survive and even grow at low temperatures, the majority of pathogenic microorganisms are hindered, which is why refrigeration is an effective method for preserving food and preventing spoilage and foodborne illnesses.

In contrast, the other choices suggest conditions that would facilitate or have no impact on microbial growth, which is inconsistent with the established understanding of microbiology and food safety practices.