Which of the following temperatures is considered optimal for short-term refrigeration storage of microbiological samples?

• A. 4°C
• B. 25°C
• C. -20°C
• D. 37°C

Answer: (A)

Verified step by step guidance

1. Understand that short-term refrigeration storage of microbiological samples aims to slow down microbial metabolism and growth without freezing the samples.
2. Recall that typical refrigeration temperatures used in microbiology labs are around 4°C, which is cold enough to reduce metabolic activity but not so cold as to cause ice crystal formation that can damage cells.
3. Recognize that 25°C is room temperature and does not provide refrigeration; it allows microbes to grow actively.
4. Note that -20°C is a freezing temperature, commonly used for long-term storage, but not ideal for short-term refrigeration because freezing can damage some samples.
5. Understand that 37°C is the optimal growth temperature for many human pathogens and would promote microbial growth rather than preserve samples.