Birbal Sahni was a `:`

Options

A. zoologist
B. founder of Central Drug Research Institute (CDRI)
C. omithologist
D. palaeobotanist

Answer

**Step-by-Step Solution:**

1. **Identify the Question:** The question asks about Birbal Sahni and his contributions or profession.

2. **Analyze the Options:**
- **Geologist:** A geologist studies the Earth, its materials, and processes. This does not align with Birbal Sahni's work.
- **Founder of Central Drug Research Institute (CDRI):** This institute was founded by Dr. Vinod, not Birbal Sahni. Therefore, this option is incorrect.
- **Ornithologist:** An ornithologist studies birds. Birbal Sahni did not work in this field, making this option incorrect.
- **Paleobotanist:** A paleobotanist studies fossil plants. This aligns perfectly with Birbal Sahni's work.

3. **Conclusion:** Based on the analysis, the correct answer is that Birbal Sahni was a **Paleobotanist**.

4. **Additional Information:** Birbal Sahni was a renowned Indian paleobotanist known for his research on fossil plants and plant evolution. He founded the Birbal Sahni Institute of Paleobotany in Lucknow in 1946.

**Final Answer:** Birbal Sahni was a Paleobotanist.

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