Entamoeba histolytica infection occurs through:

Options

A. insect bite
B. bird dropping
C. sweat
D. food or water contained with cysts

Answer

**Step-by-Step Solution:**

1. **Understanding the Organism**: Entamoeba histolytica is a type of endoparasite that infects humans and is responsible for a disease called amoebiasis.

2. **Transmission Pathways**: The infection occurs primarily through the ingestion of contaminated substances. It is crucial to identify the correct mode of transmission from the options provided.

3. **Analyzing the Options**:
- **a. Insect bite**: This is not a known transmission method for Entamoeba histolytica.
- **b. Bird dropping**: While some pathogens can be transmitted through bird droppings, Entamoeba histolytica is not one of them.
- **c. Sweat**: There is no evidence to suggest that sweat can transmit this parasite.
- **d. Food and water contaminated with cysts**: This is the primary mode of transmission for Entamoeba histolytica. The cysts are the infectious form of the parasite and are typically found in contaminated food and water.

4. **Conclusion**: Based on the analysis, the correct answer is option D: food and water contaminated with cysts.

**Final Answer**: The infection of Entamoeba histolytica occurs through D. food and water contaminated with cysts.

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