The universal natural auxin of plants is

Options

A. IBA
B. IAA
C. NAA
D. Citric auxin

Answer

**Step-by-Step Text Solution:**

1. **Understanding Auxins**: Auxins are a class of plant hormones that play a crucial role in regulating plant growth and development. They are involved in various processes such as cell elongation, root formation, and response to light and gravity.

2. **Identifying the Options**: The question provides four options: IBA, IAA, NAA, and Citric Auxin. We need to determine which of these is the universal natural auxin.

3. **Analyzing Each Option**:
- **IBA (Indole-3-butyric acid)**: This is known to be both a natural and synthetic auxin, but it is not considered the universal natural auxin.
- **IAA (Indole-3-acetic acid)**: This is the most abundant auxin found in plants and is considered the primary natural auxin. It is widely distributed in plant tissues and is essential for various growth processes.
- **NAA (Naphthalene acetic acid)**: This is a synthetic auxin and does not occur naturally in plants.
- **Citric Auxin**: This is not recognized as a natural auxin in plants.

4. **Conclusion**: Based on the analysis, the correct answer to the question "The universal natural auxin of plants is" is **IAA (Indole-3-acetic acid)**.

5. **Final Answer**: The universal natural auxin of plants is **IAA**.

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