Long day plants blossom in

Options

A. Summer
B. Autumn
C. Spring
D. 1 and 3

Answer

### Step-by-Step Solution:

1. **Understanding Long Day Plants**:
- Long day plants are those that require longer periods of light exposure to initiate flowering. Typically, these plants need more than 12 hours of light per day to bloom.

2. **Identifying Conditions for Flowering**:
- The flowering process in plants is influenced by the duration of light exposure. Longer daylight hours stimulate the flowering process in long day plants.

3. **Seasons and Daylight Duration**:
- During summer, the days are longer, which means that long day plants receive ample light exposure. This is a prime condition for these plants to blossom.
- Similarly, late spring also has longer days compared to other seasons, providing sufficient light for long day plants to flower.

4. **Analyzing the Options**:
- The question provides options: summer, late spring, and possibly other seasons.
- Since both summer and late spring have long daylight hours, they are suitable for the blossoming of long day plants.

5. **Conclusion**:
- Therefore, the correct answer is that long day plants blossom in both summer and late spring. This corresponds to option four, which includes both options one (summer) and three (late spring).

### Final Answer:
Long day plants blossom in **summer and late spring** (Option 4: both 1 and 3).

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