The hormone which promotes flowering in long day conditions and controls sex expression is

Options

A. Auxin
B. Cytokinins
C. Gibberellins
D. Ethylene.

Answer

To solve the question regarding the hormone that promotes flowering in long day conditions and controls sex expression, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Context of the Question**: The question is asking about a specific plant hormone that has two functions: promoting flowering under long day conditions and controlling sex expression in plants.

2. **Review the Options Provided**: The options given are:
- A) Auxin
- B) Cytokinins
- C) Gibberellins
- D) Ethylene

3. **Analyze Each Option**:
- **Auxin**: This hormone is primarily involved in cell elongation and does not specifically promote flowering in long day conditions.
- **Cytokinins**: These hormones are known for promoting cell division and do not directly induce flowering in long day conditions.
- **Gibberellins**: This hormone is known to promote flowering in long day conditions and is also involved in controlling sex expression in many plant species. It can induce flowering by mimicking the long day conditions.
- **Ethylene**: This hormone is primarily associated with fruit ripening and does not promote flowering in long day conditions.

4. **Select the Correct Answer**: Based on the analysis, the hormone that promotes flowering in long day conditions and controls sex expression is **Gibberellins**.

### Final Answer:
The hormone which promotes flowering in long day conditions and controls sex expression is **Gibberellins**.

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