Which one of the following is monogenetic

Options

A. Plasmodium vivax
B. Trypanosoma,gambiense
C. Leishmania donovani
D. Entamoeba gingivalis

Answer

To determine which of the given organisms is monogenetic, we need to understand what monogenetic means. Monogenetic organisms complete their life cycle in a single host without the involvement of a vector. Let's analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Monogenetic**:
- Monogenetic refers to parasites that complete their life cycle in one host and do not require a vector for transmission.

2. **Evaluating the Options**:
- **Option 1: Plasmodium vivax**
- This organism causes malaria and requires a mosquito as a vector to transfer to humans. Therefore, it is not monogenetic.

- **Option 2: Trypanosoma gambiense**
- This protozoan causes sleeping sickness and also requires the Tsetse fly as a vector for transmission to humans. Thus, it is not monogenetic.

- **Option 3: Leishmania donovani**
- This organism causes Kala Azar and uses a sand fly as a vector to infect humans. Hence, it is not monogenetic.

- **Option 4: Entamoeba gingivalis**
- This protozoan infects the human intestine and does not require a vector; it completes its life cycle entirely within a single host (humans). Therefore, it is monogenetic.

3. **Conclusion**:
- The only organism among the options that is monogenetic is **Entamoeba gingivalis**.

### Final Answer:
**Entamoeba gingivalis** is the monogenetic organism among the given options.

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