Which ones are long day plants

Options

A. Wheat, Poppy, Soyabean
B. Wheat, Poppy, Beet
C. Wheat, Oat, Soyabean
D. Wheat, Xanthium, Paddy.

Answer

To determine which plants are classified as long day plants, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of Long Day Plants**:
Long day plants are those that begin to flower when the length of daylight exceeds their critical day length. They require a longer period of light and a shorter period of darkness to initiate flowering.

2. **Identify Characteristics of Long Day Plants**:
- They flower when days are longer (typically in summer).
- They require short periods of darkness and long periods of light.

3. **Review the Given Options**:
The options provided are:
- Option A: Wheat, Poppy, Soybean
- Option B: Wheat, Poppy, Beet
- Option C: Wheat, Oat, Soybean
- Option D: Wheat, Zendium, Paddy

4. **Analyze Each Option**:
- **Option A**: Wheat (long day), Poppy (long day), Soybean (short day).
- **Option B**: Wheat (long day), Poppy (long day), Beet (long day).
- **Option C**: Wheat (long day), Oat (long day), Soybean (short day).
- **Option D**: Wheat (long day), Zendium (not commonly classified), Paddy (short day).

5. **Select the Correct Option**:
Based on the analysis, the plants that are confirmed as long day plants are found in Option B (Wheat, Poppy, Beet) and Option C (Wheat, Oat). However, since the question asks for long day plants specifically, Option B is the most accurate since all three listed are long day plants.

### Final Answer:
**Option B: Wheat, Poppy, Beet** are long day plants.

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