Select the odd one out.

Options

A. Ear drum
B. Pinna
C. Stirrup
D. tympanum

Answer

To solve the question "Select the odd one out" from the options Eardrum, Pinna, Stirrup, and Tympanum, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Function of Each Part**:
- **Eardrum**: Also known as the tympanic membrane, it is located in the middle ear and vibrates in response to sound waves.
- **Pinna**: This is the outer part of the ear that collects sound waves and directs them into the ear canal.
- **Stirrup**: This is one of the three tiny bones in the middle ear (ossicles) that help transmit sound vibrations from the eardrum to the inner ear.
- **Tympanum**: This is another term for the eardrum, which is also located in the middle ear.

2. **Categorize Each Part**:
- **Middle Ear**: Eardrum, Stirrup, Tympanum.
- **Outer Ear**: Pinna.

3. **Determine the Odd One Out**:
- The **Pinna** is the only part that is located in the outer ear, while the Eardrum, Stirrup, and Tympanum are all parts of the middle ear.

4. **Conclusion**:
- Therefore, the odd one out is **Pinna** (Option B).

### Final Answer:
**Pinna** is the odd one out.