Cell elongation in plants is caused by

Options

A. Auxin
B. Gibberellin
C. Florigen
D. Traumatin

Explanation

**Step-by-Step Solution:**

1. **Understanding Cell Elongation**: Cell elongation in plants refers to the process where plant cells increase in size, leading to growth in length of stems and roots.

2. **Identifying Plant Hormones**: Several plant hormones, also known as phytohormones, are involved in regulating growth and development in plants. The main hormones to consider for cell elongation include auxins, gibberellins, and others.

3. **Role of Auxins**: Auxins are a type of plant hormone that play a crucial role in promoting cell elongation. They are primarily produced in the tips of stems and roots and help in the elongation of cells by loosening the cell walls.

4. **Comparing Other Hormones**:
- **Gibberellins**: While gibberellins also promote growth, they are more associated with stem elongation and seed germination rather than direct cell elongation.
- **Florigen**: This hormone is primarily involved in the flowering process and does not directly influence cell elongation.
- **Traumatins**: These hormones are involved in the plant's response to wounding and stress, not in promoting cell elongation.

5. **Conclusion**: Based on the roles of these hormones, auxins are specifically responsible for cell elongation in plants.

**Final Answer**: Cell elongation in plants is caused by auxins.

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