Which among the following phytohormone is involved in the growth of the plants?

Options

A. Auxins
B. Gibberellins
C. Abscisic acid
D. Both (a) and (b)

Explanation

To determine which phytohormone is involved in the growth of plants, we can analyze the roles of different phytohormones:

1. **Identify the Phytohormones**: The main phytohormones to consider are auxin, gibberellin, and abscisic acid.

2. **Role of Auxin**: Auxin is known to promote the elongation of stems and roots. It plays a crucial role in plant growth by influencing cell elongation.

3. **Role of Gibberellin**: Gibberellin is another important phytohormone that promotes growth, specifically by elongating the internodes of the plant. This helps in increasing the height of the plant.

4. **Role of Abscisic Acid**: In contrast, abscisic acid is known to inhibit growth. It plays a role in processes such as seed dormancy and stress responses, which can prevent growth.

5. **Conclusion**: Based on the functions of these phytohormones, both auxin and gibberellin are involved in promoting the growth of plants, while abscisic acid inhibits growth.

Thus, the correct answer is that both auxin and gibberellin are the phytohormones involved in the growth of plants.

**Final Answer**: Both auxin and gibberellin are involved in the growth of plants.

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