A chemical believed to be involved in flowering is

Options

A. Gibberellin
B. Kinetin
C. Florigen
D. IBA.

Answer

**Step-by-Step Solution:**

1. **Understanding Plant Hormones**: Begin by recognizing that plants produce various hormones that regulate their growth and physiological processes. These hormones are present in small amounts and can significantly influence plant behavior.

2. **Identifying the Options**: The question provides four options: gibberellin, kinetin, florigen, and IBA. Each of these has different roles in plant physiology.

3. **Analyzing Gibberellin**: Gibberellins (abbreviated as GA) are known for promoting seed germination, inhibiting bud dormancy, and stem elongation. However, they are not primarily involved in the flowering process.

4. **Analyzing Kinetin**: Kinetin is a type of cytokinin, which is primarily involved in promoting cell division. While it plays a role in plant growth, it does not directly influence flowering.

5. **Analyzing Florigen**: Florigen is a hypothesized molecule that is believed to be involved in the flowering process. It is thought to be produced in the leaves and then transported to the apical shoot meristem, where it triggers flowering.

6. **Analyzing IBA**: IBA (indole-3-butyric acid) is an auxin that primarily aids in root elongation and apical dominance. It does not have a direct role in flowering.

7. **Conclusion**: Based on the analysis of each option, the chemical that is believed to be involved in flowering is florigen.

**Final Answer**: The chemical believed to be involved in flowering is **florigen** (Option 3).

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