Which one of the following synthetic growth regulators is used to promote synchronized flowering in pineapple

Options

A. Indole butyric acid
B. Phenyl mercuric acetate
C. Benzyl aminopurine
D. 2-Chloroethyl phosphonic acid.

Answer

To solve the question regarding which synthetic growth regulator is used to promote synchronized flowering in pineapple, we can follow these steps:

### Step 1: Understand the Question
The question asks for a specific synthetic growth regulator that is known to promote synchronized flowering in pineapple plants.

### Step 2: Analyze the Options
We have four options to consider:
1. Indole butyric acid
2. Phenyl mercuric acetate
3. Benzyl aminopurine
4. 2-chloroethyl phosphoric acid

### Step 3: Research Each Option
- **Indole butyric acid (IBA)**: This is primarily used as a rooting hormone and does not promote flowering.
- **Phenyl mercuric acetate**: This is a compound that has been used in plant studies but is not primarily known for promoting flowering.
- **Benzyl aminopurine (BAP)**: This is a cytokinin that promotes cell division and can influence flowering but is not specifically known for synchronizing flowering in pineapple.
- **2-chloroethyl phosphoric acid**: This is a synthetic form of ethylene, which is a plant hormone known to regulate various growth processes, including flowering.

### Step 4: Identify the Correct Answer
From the analysis, 2-chloroethyl phosphoric acid is recognized as a synthetic ethylene that promotes synchronized flowering in pineapple. Therefore, the correct answer is:

**2-chloroethyl phosphoric acid**

### Step 5: Conclusion
The synthetic growth regulator used to promote synchronized flowering in pineapple is 2-chloroethyl phosphoric acid.

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