A sythetic growth regulator used to promote synchronized flowering in pineapples :-

Options

A. Benzyl aminopurine
B. Phenyl mercuric acetate
C. Indolw butyric acid
D. Ethephon

Answer

To solve the question regarding the synthetic growth regulator used to promote synchronized flowering in pineapples, we will analyze the options provided and identify the correct one step by step.

### Step 1: Understand the Question
The question asks for a synthetic growth regulator that promotes synchronized flowering in pineapples. We need to identify which of the provided options serves this function.

### Step 2: Analyze the Options
1. **Benzyl Aminopurine**: This is a cytokinin that promotes cell division but is not specifically known for inducing flowering in pineapples.

2. **Phenyl Mercuric Acetate**: This compound is primarily used as a disinfectant and does not function as a growth regulator in plants.

3. **Indole Butyric Acid (IBA)**: This is an auxin that promotes root development and cell elongation but is not specifically associated with flowering in pineapples.

4. **Ethylene (Ethephon)**: This is a plant hormone that regulates various growth processes, including flowering and fruit ripening. It is known to induce flowering in pineapples and is used to synchronize flowering in commercial pineapple cultivation.

### Step 3: Identify the Correct Answer
Based on the analysis, the correct answer is **Ethephon**. It is the synthetic growth regulator that promotes synchronized flowering in pineapples.

### Final Answer
The synthetic growth regulator used to promote synchronized flowering in pineapples is **Ethephon**.

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