Caecum/colon is vestigeal in man.

Explanation

### Step-by-Step Solution:

1. **Understanding Vestigial Organs**:
- Vestigial organs are those that have lost most or all of their original function through the course of evolution. In humans, these organs are remnants of features that were functional in our ancestors.

2. **Identifying the Caecum**:
- The caecum is a pouch connected to the junction of the small and large intestines. In humans, it is often associated with the appendix, which is a small, tube-like structure that extends from the caecum.

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