Which of the following organ in man is vestigial:

Options

A. Pinna
B. Wisdom tooth
C. Fossa ovalis
D. Ileum

Answer

To determine which organ in humans is vestigial, we will analyze each of the given options one by one.

### Step-by-Step Solution:

1. **Identify the Options**: The question provides several options. We need to evaluate each one to find out which is vestigial.

2. **Option 1: Ear Pinna**
- The ear pinna is the outer part of the ear that helps in capturing sound waves. It is functional and not vestigial.
- **Conclusion**: This option is incorrect.

3. **Option 2: Wisdom Tooth**
- Wisdom teeth, also known as third molars, were useful for our ancestors who had a diet that required more chewing of tough plant material. Over time, as human diets changed, these teeth became less necessary and often do not have enough space to emerge properly in modern humans. Therefore, they are considered vestigial.
- **Conclusion**: This option is correct.

4. **Option 3: Fossa Ovalis**
- The fossa ovalis is a remnant of the foramen ovale, which is a structure in the fetal heart that allows blood to bypass the lungs. After birth, it usually closes and becomes the fossa ovalis. While it has a historical significance, it is not considered vestigial in the same way as wisdom teeth.
- **Conclusion**: This option is incorrect.

5. **Option 4: Ileum**
- The ileum is the final part of the small intestine and plays a crucial role in the absorption of nutrients. It is a functional organ and not vestigial.
- **Conclusion**: This option is incorrect.

### Final Answer:
The correct answer is **Option 2: Wisdom Tooth**.

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