Carriers of Enamoeba histolytica are

Options

A. Anopheles
B. Cattle
C. House flies
D. Healthy human hosts.

Answer

### Step-by-Step Solution:

1. **Understanding the Organism**: Antamoeba histolytica is a unicellular eukaryotic organism that causes amoebiasis, an infection of the colon or large intestine in humans.

2. **Transmission of Amoebiasis**: The primary mode of transmission for Antamoeba histolytica is through contaminated food or water. When a person ingests food or water that has been contaminated with the cysts of the organism, they can become infected.

3. **Role of Carriers**: Carriers are organisms that harbor a pathogen without showing symptoms of the disease. In the case of Antamoeba histolytica, healthy human hosts can carry the organism without exhibiting symptoms of amoebiasis.

4. **Examining the Options**:
- **Anopheles**: This is a genus of mosquitoes known to transmit malaria, not amoebiasis.
- **Cattle**: While they can carry various diseases, they are not known carriers of Antamoeba histolytica.
- **House Flies**: They can spread various pathogens but are not specific carriers for Antamoeba histolytica.
- **Healthy Human Hosts**: These individuals can carry the cysts of Antamoeba histolytica without showing symptoms, making them the correct answer.

5. **Conclusion**: Based on the information, the correct answer to the question "Carriers of Antamoeba histolytica are" is **healthy human hosts**.