Cryopreservation is:

Options

A. Preservation of living beings in chemicals
B. preservation through gases
C. preservation at very low temperature
D. Preservation at high temperature

Answer

**Step-by-Step Solution:**

1. **Understanding Cryopreservation**: Cryopreservation refers to the process of preserving cells, tissues, or any biological constructs by cooling them to very low temperatures. This process helps in preventing damage that could occur due to various factors.

2. **Evaluating the Options**:
- **Option 1**: Preservation of living beings in chemical - This is not accurate as cryopreservation specifically involves low temperatures, not chemicals.
- **Option 2**: Preservation through gases - This does not describe cryopreservation, which is focused on low temperatures rather than gases.
- **Option 3**: Preservation at very low temperatures - This is the correct definition of cryopreservation.
- **Option 4**: Preservation at high temperatures - This contradicts the concept of cryopreservation, as it involves low, not high, temperatures.

3. **Conclusion**: Based on the definitions and evaluations of the options, the correct answer is that cryopreservation is the preservation at very low temperatures.

**Final Answer**: Cryopreservation is preservation at very low temperatures (Option 3).

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