Mark the incorrect statement w.r.t. infection of Entamoeba histolytica

Options

A. It is a protozoan parasite of human
B. It is characterised by constipation and abdominal pain
C. It is a parasite in small intestine of man
D. Houseflies act as mechanical carriers and serve to transmit the parasite from faeces of infected person to food and food products

Explanation

To determine the incorrect statement regarding the infection of Entamoeba histolytica, we will analyze each of the provided statements one by one.

### Step-by-Step Solution:

1. **Identify the Nature of Entamoeba histolytica**:
- Entamoeba histolytica is a protozoan parasite that primarily infects humans.
- **Statement**: "It is a protozoan parasite of humans."
- **Evaluation**: This statement is correct.

2. **Examine Symptoms of Infection**:
- The infection caused by Entamoeba histolytica is known as amoebic dysentery or amoebiasis.
- Common symptoms include diarrhea, abdominal pain, and constipation.
- **Statement**: "It is characterized by constipation and abdominal pain."
- **Evaluation**: This statement is also correct as these are indeed symptoms of the infection.

3. **Assess the Role of House Flies**:
- House flies can act as mechanical carriers of the parasite, transmitting it from feces of infected individuals to food and water.
- **Statement**: "House flies act as the mechanical carriers and serve to transmit the parasite from feces of infected person to food and food products."
- **Evaluation**: This statement is correct as well.

4. **Determine the Location of the Parasite**:
- Entamoeba histolytica primarily resides in the large intestine of humans, not the small intestine.
- **Statement**: "It is a parasite in the small intestine of man."
- **Evaluation**: This statement is incorrect because the parasite actually inhabits the large intestine.

### Conclusion:
The incorrect statement regarding the infection of Entamoeba histolytica is: "It is a parasite in the small intestine of man."

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