Tetranucleated cyst stage is found in

Options

A. Entamoeba coli
B. Entamoeba histolytica
C. Leishmania
D. Trypanosoma

Answer

To determine which organism has a tetranucleated cyst stage, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Term "Tetranucleated":**
- The term "tetranucleated" refers to a cyst that contains four nuclei. This is a key characteristic we need to identify in the organisms listed in the options.

2. **Analyzing the Options:**
- We have four options:
a. Entamoeba coli
b. Entamoeba histolytica
c. Leishmania
d. Trypanosoma

3. **Identifying the Cyst Stages:**
- **Entamoeba coli**: This organism does have a cyst stage, and it can have a tetranucleated form.
- **Entamoeba histolytica**: This organism is known for its pathogenicity and also has a tetranucleated cyst stage.
- **Leishmania**: This organism does not have a tetranucleated cyst stage; it has a different life cycle involving promastigotes and amastigotes.
- **Trypanosoma**: Similar to Leishmania, Trypanosoma does not have a tetranucleated cyst stage; it has a flagellated form.

4. **Determining the Correct Answer:**
- Both Entamoeba coli and Entamoeba histolytica can form tetranucleated cysts. However, the question is likely focusing on the pathogenic form, which is Entamoeba histolytica, as it is the one associated with infections in humans.

5. **Final Conclusion:**
- The tetranucleated cyst stage is found in **Entamoeba histolytica**.

### Final Answer:
**Option B: Entamoeba histolytica**

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