A technique in which sperm are stored for a long duration is

Options

A. incubator
B. cryopreservation
C. deep freezing
D. all of these

Answer

To solve the question "A technique in which sperm are stored for a long duration is," we will analyze the provided options step by step.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for a technique specifically used for the long-term storage of sperm.

2. **Analyzing the Options**:
- **Option A: Incubator**: An incubator is typically used to maintain a controlled environment for the growth of cells or bacteria at a specific temperature (usually around 37°C). It is not suitable for long-term storage of sperm.

- **Option B: Cryopreservation**: This is a technique that involves cooling and storing cells, including sperm, at very low temperatures (often below -196°C using liquid nitrogen). This method allows for the long-term preservation of sperm viability and function.

- **Option C: Deep Freezing**: While deep freezing can refer to storing biological materials at low temperatures, it is not a specific technique for sperm storage. It is often associated with the preservation of other biological materials but is less specific than cryopreservation.

- **Option D: All of these**: Since not all the options are suitable for long-term sperm storage, this option cannot be correct.

3. **Conclusion**: Based on the analysis, the most appropriate technique for the long-term storage of sperm is **cryopreservation**.

### Final Answer:
**Option B: Cryopreservation**

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