The active form of Entamoeba-histolytica feeds upon

Options

A. Food in intestine
B. Blood only
C. Erythrocytes, mucosa and submucosa of colon
D. Mucosa and submucosa of colon only

Answer

### Step-by-Step Solution:

1. **Understanding Entamoeba histolytica**:
- Entamoeba histolytica is a pathogenic amoeba that primarily infects humans. It is known for causing intestinal diseases, particularly amoebic dysentery.

2. **Identifying the Phylum**:
- This organism belongs to the phylum Protozoa. It is important to note that it is a single-celled organism that can cause significant health issues.

3. **Pathogenic Mechanism**:
- Entamoeba histolytica invades the mucosal and submucosal layers of the large intestine. This invasion leads to tissue damage and can result in dysentery.

4. **Feeding Behavior**:
- The active form of Entamoeba histolytica feeds on the tissues it invades, which includes the mucosa and submucosa of the colon, as well as erythrocytes (red blood cells). This feeding behavior is crucial for its survival and pathogenicity.

5. **Eliminating Incorrect Options**:
- The organism does not primarily feed on food in the intestine or blood alone. Therefore, options that suggest it feeds only on these are incorrect.

6. **Correct Answer**:
- The correct answer is that Entamoeba histolytica feeds upon erythrocytes, mucosa, and submucosa of the colon.

### Final Answer:
The active form of Entamoeba histolytica feeds upon erythrocytes, mucosa, and submucosa of the colon.

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