Diseases of human being caused by protozoan parasites are
A. amoebiasis
B. malaria
C. trypanosomiasis
D.typhoid

Options

A. A,B
B. A,B,C
C. A,C,D
D. A,B,C,D

Answer

To answer the question regarding diseases caused by protozoan parasites, we will analyze each option provided:

1. **Amoebiasis**: This disease is caused by the protozoan parasite *Entamoeba histolytica*. It primarily affects the intestines and can lead to severe dysentery. Therefore, amoebiasis is indeed caused by a protozoan parasite.

2. **Malaria**: This disease is caused by protozoan parasites of the genus *Plasmodium*. It is transmitted through the bite of infected female Anopheles mosquitoes and leads to symptoms such as fever, chills, and flu-like illness. Hence, malaria is also caused by a protozoan parasite.

3. **Trypanosomiasis**: Also known as sleeping sickness (in Africa) and Chagas disease (in the Americas), this disease is caused by protozoan parasites of the genus *Trypanosoma*. It is transmitted by tsetse flies and triatomine bugs, respectively. Thus, trypanosomiasis is another disease caused by a protozoan parasite.

4. **Typhoid**: This disease is caused by the bacterium *Salmonella typhi*, not a protozoan parasite. It is transmitted through contaminated food and water. Therefore, typhoid is not caused by a protozoan parasite.

### Conclusion:
The diseases caused by protozoan parasites from the options given are:
- A. Amoebiasis
- B. Malaria
- C. Trypanosomiasis

The correct answers are A, B, and C.