Which of the following is endoparasitic protozoan?

Options

A. Paramoecium
B. Euglena
C. Amoeba
D. Plasmodium

Answer

To determine which of the following is an endoparasitic protozoan, we will analyze each option provided: Paramecium, Euglena, Amoeba, and Plasmodium.

### Step 1: Understand the definitions
- **Parasites** are organisms that obtain nourishment from a living host. They can be classified into two types:
- **Ectoparasites**: These live outside the body of the host (e.g., ticks, leeches).
- **Endoparasites**: These live inside the body of the host (e.g., Ascaris, Plasmodium).

### Step 2: Analyze each option
1. **Paramecium**:
- Paramecium is a protozoan that is free-living and not a parasite. It primarily lives in freshwater environments and feeds on bacteria and small particles.

2. **Euglena**:
- Euglena is also a free-living organism that can photosynthesize. It is not a parasite and is typically found in aquatic environments.

3. **Amoeba**:
- Amoeba is another free-living protozoan. While some species can cause diseases, the common amoeba is not classified as a parasite.

4. **Plasmodium**:
- Plasmodium is a well-known endoparasitic protozoan that causes malaria. It lives inside the red blood cells of its host and is transmitted by the bite of infected mosquitoes.

### Step 3: Conclusion
After analyzing all the options, the only endoparasitic protozoan among the given choices is **Plasmodium**. Therefore, the correct answer is **Plasmodium** (option 4).

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