Appendix is a part of:

Options

A. ileum
B. duodenum
C. caecum
D. colon

Explanation

### Step-by-Step Solution:

1. **Understanding the Appendix**: The appendix is recognized as a vestigial organ, meaning it has lost its original function over time but is still present in the body.

2. **Location of the Appendix**: The appendix is specifically located at the junction of the small intestine and the large intestine.

3. **Identifying the Correct Part**: The appendix is attached to the cecum, which is the first part of the large intestine.

4. **Clarifying Other Intestinal Parts**:
- The ileum is the last part of the small intestine.
- The duodenum is the first part of the small intestine.
- Therefore, neither the ileum nor the duodenum is where the appendix is found.

5. **Conclusion**: Based on the above information, we conclude that the appendix is a part of the cecum.

### Final Answer:
The appendix is a part of the cecum.

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