If a tree flowers thrice in a year (October, January and july) in nothern india, it is said to be

Options

A. Photo- and thermo-sensitive
B. Photo- and thermo-insensitive
C. Photosensitive but thermo-insensitive
D. Thermosensitive but photo-insensitive.

Answer

To determine the classification of a tree that flowers thrice a year (in October, January, and July) in Northern India, we need to analyze the factors influencing flowering in plants.

### Step-by-Step Solution:

1. **Understanding Flowering Factors**:
- Flowering in plants is influenced by two main factors: photoperiodism and vernalization.
- Photoperiodism refers to how the length of day and night affects flowering.
- Vernalization is the process where flowering is promoted by exposure to a prolonged period of cold temperatures.

2. **Identifying Photoperiodism**:
- In this case, the tree flowers in October, January, and July. This indicates that it is not restricted to a specific season and can flower in different photoperiods.
- Since it flowers in winter (January) and summer (July), it suggests that the tree is not dependent on long days or short days for flowering.

3. **Analyzing Vernalization**:
- The fact that the tree flowers in January, which is typically a colder month, suggests that it may require lower temperatures to trigger flowering.
- This indicates that the tree is likely thermosensitive, meaning it responds to temperature changes.

4. **Conclusion on Sensitivity**:
- Since the tree flowers irrespective of the day length (as it flowers in both summer and winter), it is photo insensitive.
- However, it is thermosensitive because it responds to temperature changes.

5. **Selecting the Correct Option**:
- Based on the analysis, the tree is identified as thermosensitive but photo insensitive.
- Therefore, the correct answer is: **Thermosensitive but photo insensitive**.

### Final Answer:
The tree is said to be **thermosensitive but photo insensitive**.