An intracellular parasite is

Options

A. Entamoeba
B. Ascaris
C. Plasmodium
D. Both (a) and (b)

Explanation

**Step-by-Step Solution:**

1. **Understanding Parasites**: Begin by defining what a parasite is. Parasites are organisms that depend on another organism (the host) for survival and nutrition. They often lack the necessary organs to perform metabolic functions independently.

2. **Types of Parasites**: Recognize that there are different types of parasites, including intracellular and extracellular parasites. Intracellular parasites live within the cells of their host, while extracellular parasites live outside the cells.

3. **Identifying Intracellular Parasites**: From the given options, we need to identify which of the mentioned organisms is an intracellular parasite. The options provided are Entamoeba, Caris, and Plasmodium.

4. **Analyzing the Options**:
- **Entamoeba**: This is a protozoan that causes amoebiasis, primarily affecting the intestine. It does not live inside the cells but rather in the intestinal lumen.
- **Caris**: This refers to a type of nematode (roundworm) that also lives in the intestine and can cause symptoms similar to amoebiasis. Like Entamoeba, it does not live inside the cells.
- **Plasmodium**: This is a protozoan that causes malaria and is known to be an intracellular parasite. It survives and reproduces within red blood cells.

5. **Conclusion**: Based on the analysis, Plasmodium is the only organism among the options that is classified as an intracellular parasite, as it resides within the cells of the host (specifically, red blood cells).

6. **Final Answer**: Therefore, the correct answer to the question "An intracellular parasite is" is **Plasmodium**.

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