Sir Ronald Ross discovered that

Options

A. malaria is caused by protozoans parasite
B. malaria is caused by foul air
C. four species of Plasmodium cause malaria
D. malaria is transmitted by female Anopheles.

Answer

**Step-by-Step Solution:**

1. **Identify Sir Ronald Ross**: Sir Ronald Ross was a British physician born in India, known for his significant contributions to the understanding of malaria.

2. **Understand the Cause of Malaria**: He discovered that malaria is caused by a protozoan parasite known as Plasmodium.

3. **Transmission of Malaria**: Ross identified that the malaria parasite is transmitted to humans through the bite of infected female Anopheles mosquitoes.

4. **Significance of the Discovery**: This groundbreaking discovery was made on August 20, 1897, and it was pivotal in the field of medicine, leading to further research on malaria prevention and treatment.

5. **Recognition of the Discovery**: For his work, Sir Ronald Ross was awarded the Nobel Prize in Physiology or Medicine in 1902. The day of his discovery is celebrated annually as World Mosquito Day.

6. **Conclusion**: The correct statement regarding Sir Ronald Ross's discovery is that malaria is transmitted by female Anopheles mosquitoes.

**Final Answer**: Sir Ronald Ross discovered that malaria is transmitted by female Anopheles mosquitoes.

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