Chyrsanthemums flower in winter because

Options

A. They are short day plants
B. They required low temperature treatment
C. They are long day plants
D. Both A and B.

Answer

### Step-by-Step Solution:

1. **Understanding Plant Categories**: Plants can be categorized based on their flowering response to light duration. The two main categories are short day plants and long day plants.

2. **Definition of Short Day Plants**: Short day plants are those that require a longer duration of darkness (or shorter duration of light) to initiate flowering. They typically flower in the autumn and winter months.

3. **Chrysanthemums as Short Day Plants**: Chrysanthemums are classified as short day plants. They require specific conditions, including lower temperatures and longer periods of darkness, to bloom.

4. **Temperature Requirements**: In addition to the light conditions, short day plants like chrysanthemums often thrive in cooler temperatures, which further supports their flowering during the winter season.

5. **Conclusion**: Since chrysanthemums flower in winter due to their classification as short day plants that require low temperatures and longer periods of darkness, the correct answer to the question is that they flower in winter because they are short day plants and require low temperature treatment.

### Final Answer:
Chrysanthemums flower in winter because they are short day plants that require low temperature treatment.

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