The correct answer is D. Trypanosoma.
Trypanosoma brucei is a protozoan parasite that causes African trypanosomiasis, also known as sleeping sickness. It is transmitted to humans by the bite of infected tsetse flies. The disease is characterized by fever, headache, and fatigue. In the later stages, it can cause neurological problems, coma, and death.
Plasmodium is a genus of protozoan parasites that cause malaria. They are transmitted to humans by the bite of infected mosquitoes. Malaria is a major public health problem in many parts of the world, and it is estimated to cause over 400,000 deaths each year.
Entamoeba is a genus of protozoan parasites that can cause amoebic dysentery. They are transmitted to humans by the ingestion of contaminated food or water. Amoebic dysentery is a diarrheal disease that can be severe, and it can be fatal in some cases.
Giardia is a genus of protozoan parasites that can cause giardiasis. They are transmitted to humans by the ingestion of contaminated food or water. Giardiasis is a diarrheal disease that can be mild or severe.
In conclusion, the correct answer is D. Trypanosoma.