Read the following statements.
A. ABA is derived from violaxanthin and is also known as anti GA hormone.
B. Ethylene increases the number of male flowers.
C. Extrinsic factors like temperature and light control plant growth and development via PGRs.
D. GA, is used to speed up the malting process in brewing industry.
Choose the correct option.

Options

A. Only A is incorrect
B. Only B is incorrect
C. A, B and C are incorrect
D. B, C and D are incorrect

Answer

To solve the question, we need to analyze each of the four statements provided and determine their validity.

### Step-by-Step Solution:

1. **Analyze Statement A:**
- Statement A claims that ABA (abscisic acid) is derived from violaxanthin and is known as the anti-GA hormone.
- **Evaluation:** This statement is true. ABA is indeed derived from violaxanthin and is known to inhibit growth, acting antagonistically to gibberellins (GA).

2. **Analyze Statement B:**
- Statement B states that ethylene increases the number of male flowers.
- **Evaluation:** This statement is false. Ethylene is known to promote femaleness in flowers, while gibberellins promote maleness.

3. **Analyze Statement C:**
- Statement C mentions that extrinsic factors like temperature and light control plant growth and development via PGRs (Plant Growth Regulators).
- **Evaluation:** This statement is true. Extrinsic factors such as temperature and light do influence plant growth and development through the action of PGRs.

4. **Analyze Statement D:**
- Statement D states that GA (gibberellins) is used to speed up the malting process in the brewing industry.
- **Evaluation:** This statement is true. Gibberellins are indeed used to accelerate the malting process in brewing.

### Conclusion:
- From the analysis, we find that:
- Statement A: True
- Statement B: False
- Statement C: True
- Statement D: True

Thus, the correct option is that only statement B is incorrect, while statements A, C, and D are correct.

### Final Answer:
The correct option is: **Only B is incorrect.**

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