BirBal Sahni worked on `:`

Options

A. Algae
B. Fossil plants
C. Angiosperms
D. Bryophytes

Answer

**Step-by-Step Solution:**

1. **Identify the Subject of the Question**: The question asks about the work of BirBal Sahni, specifically what he focused on in his research.

2. **Review the Options Provided**: The options given are:
- A) Algae
- B) Fossil plants
- C) Angiosperms
- D) Bryophytes

3. **Recall Relevant Information**: BirBal Sahni was an Indian paleobotanist known for his studies related to fossils in the Indian subcontinent. His major contributions were specifically in the field of fossil plants and plant evolution.

4. **Analyze Each Option**:
- **Option A (Algae)**: There is no significant record of Sahni working on algae.
- **Option B (Fossil plants)**: This aligns with Sahni's known contributions to paleobotany and his studies on fossil plants in India.
- **Option C (Angiosperms)**: While angiosperms are a part of plant evolution, Sahni's primary focus was not specifically on angiosperms.
- **Option D (Bryophytes)**: Similar to algae, there is no notable association of Sahni with bryophytes.

5. **Select the Correct Answer**: Based on the analysis, the correct answer is **Option B: Fossil plants**.

**Final Answer**: BirBal Sahni worked on **fossil plants**.

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