Causative agent of amoebiasis is

Options

A. Amoeba proteus
B. Entamoeba histolytica
C. Entamoeba coli
D. Entamoeba gingivalis

Answer

To determine the causative agent of amoebiasis, we need to analyze the options provided and understand the characteristics of the organisms listed.

### Step-by-Step Solution:

1. **Understanding Amoebiasis**:
- Amoebiasis, also known as amoebic dysentery, is an intestinal infection caused by certain types of amoebae. It is important to note that this disease is often associated with poor sanitary conditions.

2. **Analyzing the Options**:
- **Option 1: Amoeba proteus**: This is a non-parasitic amoeba and does not cause any diseases in humans. Therefore, it cannot be the causative agent of amoebiasis.
- **Option 2: Entamoeba histolytica**: This is a pathogenic amoeba known to cause amoebiasis. It is the most recognized causative agent of this disease and is associated with dysentery.
- **Option 3: Entamoeba coli**: While this is a species of amoeba, it is generally non-pathogenic and does not cause amoebiasis. It is often confused with Escherichia coli, which is a bacteria.
- **Option 4: Entamoeba gingivalis**: This amoeba is associated with periodontal disease but is not the primary causative agent of amoebiasis.

3. **Conclusion**:
- After analyzing all the options, the only organism that is known to cause amoebiasis is **Entamoeba histolytica**. Therefore, the correct answer is **Entamoeba histolytica**.

### Final Answer:
The causative agent of amoebiasis is **Entamoeba histolytica**.

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