Sir Ronald Ross is famous for discovery of

Options

A. Erythrocyts cycle of Plasmodium
B. Oocysts on stomach of female Anopheles
C. Transmission of malaria by female Anopheles
D. Both B and C.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the discovery made by Sir Ronald Ross. We need to identify what he is famous for in relation to malaria and its transmission.

2. **Reviewing the Options**: The options provided are:
- A) Erythrocyte cycle of Plasmodium
- B) Oocytes in the stomach of female Anopheles
- C) Transmission of malaria by female Anopheles
- D) Both B and C

3. **Analyzing Each Option**:
- **Option A**: The erythrocyte cycle of Plasmodium refers to the lifecycle of the malaria parasite within red blood cells. This was not discovered by Ross.
- **Option B**: Oocytes in the stomach of female Anopheles refers to a stage in the lifecycle of the malaria parasite, but this is not the primary discovery attributed to Ross.
- **Option C**: This option states that Ross discovered the transmission of malaria by female Anopheles mosquitoes. This is indeed true, as he identified that the malaria parasite is present in these mosquitoes and is responsible for transmitting malaria.
- **Option D**: This option suggests both B and C are correct, but since B is not the primary discovery, this option is incorrect.

4. **Conclusion**: Based on the analysis, the correct answer is **Option C**: "Transmission of malaria by female Anopheles."

5. **Historical Context**: Sir Ronald Ross was awarded the Nobel Prize in 1902 for his work on malaria, specifically for demonstrating that the malaria parasite is transmitted by female Anopheles mosquitoes.

**Final Answer**: Sir Ronald Ross is famous for the discovery of the transmission of malaria by female Anopheles mosquitoes (Option C).

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