National botanical garden of Lucknow is now known as :

Options

A. Royal botanical garden
B. Indian botanical garden
C. National botanical research institute
D. All of the above

Answer

**Step-by-Step Solution:**

1. **Identify the Location**: The question asks about the National Botanical Garden located in Lucknow, India.

2. **Historical Context**: This garden was established in 1789 by Nawab of Oudh, Sadat Ali Khan. Understanding its history helps to appreciate its significance.

3. **Current Name**: The National Botanical Garden of Lucknow is now known as the National Botanical Research Institute. This reflects its evolution from a garden to a research institution.

4. **Evaluate Options**:
- Option A: Royal Botanical Garden - This is incorrect as it refers to a different botanical garden located in West Bengal.
- Option B: Indian Botanical Garden - This is also incorrect as it is a separate entity and not located in Lucknow.
- Option C: National Botanical Research Institute - This is the correct answer as it is the current name of the National Botanical Garden of Lucknow.
- Option D: All of Debu - This option is incorrect and does not pertain to the question.

5. **Conclusion**: After evaluating the options, the correct answer is the National Botanical Research Institute.

**Final Answer**: The National Botanical Garden of Lucknow is now known as the National Botanical Research Institute.

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