Plants which disregard the requirement of a definite day length for flowering are called

Options

A. Short day plants
B. Long day plants
C. Day neutral plants
D. Long-short day plants.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about plants that do not require a specific day length to flower. This means we are looking for a category of plants that can flower regardless of whether the day is long or short.

2. **Identifying the Options**: The options provided are:
- Short day plants
- Long day plants
- Day neutral plants
- Long short day plants

3. **Defining Each Option**:
- **Short Day Plants**: These plants require a shorter day length (longer nights) to initiate flowering.
- **Long Day Plants**: These plants require a longer day length (shorter nights) to initiate flowering.
- **Day Neutral Plants**: These plants can flower regardless of the day length; they do not depend on specific light or dark periods.
- **Long Short Day Plants**: These plants require both short and long day lengths for flowering, depending on the variety.

4. **Analyzing the Correct Option**: Since the question specifically asks for plants that disregard the requirement of a definite day length for flowering, the correct answer must be "Day Neutral Plants." These plants can flower without being affected by the length of the day or night.

5. **Conclusion**: Therefore, the correct answer to the question is **Day Neutral Plants**.

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