Which is vestigial organ in man :

Options

A. Pinna
B. Pinna muscles
C. Ileum
D. Teeth

Answer

**Step-by-Step Solution:**

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

2. **Analyzing the Options**:
- **Option 1: Pinna** - The pinna is the outer part of the ear that helps in capturing sound waves and directing them into the ear canal. This organ is functional and not vestigial.
- **Option 2: Plica Semilunaris (Pineal Muscles)** - This is a remnant of the nictitating membrane found in other animals. In humans, it does not serve a significant purpose and is considered vestigial.
- **Option 3: Ileum** - The ileum is the final part of the small intestine, responsible for nutrient absorption. It is a functional organ and not vestigial.
- **Option 4: Teeth** - Teeth are essential for mastication (chewing) and are not vestigial.

3. **Identifying the Correct Answer**: Based on the analysis, the correct answer is **Option 2: Pineal Muscles**. These are considered vestigial as they no longer serve their original purpose in humans.

**Final Answer**: The vestigial organ in man is the **Pineal Muscles**.

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