Hormone responsible for growth of the root in micropropagation is

Options

A. auxin
B. gibberellin
C. cytokinin
D. abscisis acid.

Explanation

**Step-by-Step Solution:**

1. **Understanding Micropropagation**: Micropropagation is a technique used to produce new plants from a small piece of the parent plant, such as a cell or tissue. This process allows for the cloning of plants, ensuring that the new plants are genetically identical to the parent.

2. **Role of Hormones in Plant Growth**: In plants, hormones play a crucial role in regulating growth and development. Different hormones are responsible for various aspects of growth, including root development.

3. **Identifying the Relevant Hormone**: Among the various plant hormones, auxin is specifically known for its role in promoting root growth. It is produced in the tips of shoots and roots and facilitates the elongation of cells, which leads to root development.

4. **Conclusion**: Therefore, the hormone responsible for the growth of roots in micropropagation is auxin.

**Final Answer**: Auxin is the hormone responsible for the growth of the root in micropropagation.

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