The main function of abscisic acid in plants is to

Options

A. increase the length of cells
B. promote cell divison
C. inhibt growth
D. promote growth of stem

Explanation

**Step-by-Step Solution:**

1. **Identify the Substance**: The question asks about the main function of abscisic acid in plants. Abscisic acid is classified as a phytohormone, which is a type of plant hormone.

2. **Understand Phytohormones**: There are five main types of phytohormones in plants: auxin, gibberellin, cytokinin, ethylene, and abscisic acid. Among these, auxin, gibberellin, cytokinin, and ethylene are known as growth-promoting hormones.

3. **Characterize Abscisic Acid**: Unlike the other four hormones, abscisic acid is primarily an inhibiting hormone. Its main role is to inhibit growth in plants.

4. **Functions of Abscisic Acid**:
- It inhibits growth, which means it stops or slows down the growth processes in plants.
- It induces dormancy in seeds, especially under unfavorable environmental conditions (like drought or extreme temperatures).
- It contributes to the process of leaf and fruit abscission (the dropping of leaves and fruits).

5. **Evaluate the Options**: Based on the understanding of abscisic acid's functions:
- It does not increase the length of cells.
- It does not promote cell division.
- It does inhibit growth.
- It does not promote growth.

6. **Select the Correct Answer**: The correct answer is that the main function of abscisic acid in plants is to inhibit growth.

**Final Answer**: The main function of abscisic acid in plants is to inhibit growth.

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