Micropropagation involves

Options

A. vegetative multiplication of plants by using microoganisms
B. vegetative multiplication of plants by using small explants
C. vegetative multiplication of plants by using microspores
D. non-vegetative multiplication of plants by using microspores and megaspores.

Explanation

**Step-by-Step Solution:**

1. **Understanding Micropropagation**: Micropropagation is a technique used in plant biotechnology that involves the cultivation of plant cells, tissues, or organs in a controlled environment (in vitro) to produce new plants.

2. **Definition of Key Terms**:
- **Micro**: Refers to something small or minute.
- **Propagation**: Refers to the process of multiplying or reproducing plants.

3. **Identifying the Process**: The process of micropropagation specifically involves vegetative multiplication, which means producing new plants from parts of existing plants rather than from seeds.

4. **Use of Explants**: In micropropagation, small pieces of plant tissue known as explants are used. These explants can come from various parts of the plant such as stems, leaves, or roots.

5. **In Vitro Conditions**: The multiplication occurs under sterile conditions in a laboratory setting, which allows for rapid growth and development of the new plants.

6. **Evaluating Options**:
- **Option A**: Vegetative multiplication of plants by using microorganisms - Incorrect, as microorganisms are not used in micropropagation.
- **Option B**: Vegetative multiplication of plants by using small explants - Correct, as this accurately describes the process of micropropagation.
- **Option C**: Vegetative multiplication of plants by using microspores - Incorrect, as microspores are not involved in this process.
- **Option D**: Non-vegetative multiplication of plants by using microspores and megaspores - Incorrect, as this does not relate to the definition of micropropagation.

7. **Conclusion**: The correct answer is **Option B**: Vegetative multiplication of plants by using small explants.

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