The following PGR helps in early seed production in conifers' is

Options

A. auxins
B. gibberellins
C. ABA
D. `C_2H_4`

Answer

To solve the question "The following PGR helps in early seed production in conifers," we will analyze the provided options one by one to identify the correct plant growth regulator (PGR).

### Step-by-Step Solution:

1. **Identify the Options**: The question provides four options to choose from. We need to evaluate each one to determine which PGR is responsible for early seed production in conifers.

2. **Evaluate Auxins**:
- Auxins are known for promoting apical dominance and cell elongation.
- **Conclusion**: Auxins do not significantly contribute to early seed production in conifers.
- **Status**: Incorrect option.

3. **Evaluate Gibberellins**:
- Gibberellins are known to promote flowering and seed development. They play a crucial role in breaking dormancy and initiating seed production.
- **Conclusion**: Gibberellins are indeed responsible for early seed production in conifers.
- **Status**: Correct option.

4. **Evaluate Abscisic Acid**:
- Abscisic acid is primarily involved in seed development and maturation. It helps in the response to stress and regulates the closure of stomata.
- **Conclusion**: Abscisic acid does not promote early seed production.
- **Status**: Incorrect option.

5. **Evaluate Ethylene**:
- Ethylene is a hormone that primarily regulates fruit ripening and is involved in various developmental processes, but it does not play a significant role in seed production.
- **Conclusion**: Ethylene is not responsible for early seed production in conifers.
- **Status**: Incorrect option.

6. **Final Conclusion**: Based on the evaluations, the correct answer is **Gibberellins**, as they help in early seed production in conifers.

### Final Answer:
The following PGR that helps in early seed production in conifers is **Gibberellins**.

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