In which of the following tympanum is absent:-

Options

A. Birds
B. Frog
C. Lizard
D. Snake

Answer

To solve the question regarding which animal lacks a tympanum, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Tympanum**: The tympanum is an external hearing structure found in many animals. It plays a crucial role in detecting sound waves and is often referred to as the eardrum.

2. **Analyzing the Options**:
- **Option 1: Birds**: Birds possess a tympanum, which aids in their hearing capabilities. Therefore, this option is incorrect.
- **Option 2: Frogs**: Frogs also have a tympanum that helps them in hearing. Thus, this option is also incorrect.
- **Option 3: Lizards**: Lizards are equipped with a tympanum as well, making this option incorrect too.
- **Option 4: Snakes**: Snakes do not have a tympanum. Instead, they rely on other sensory mechanisms for detecting vibrations and sounds. Hence, this option is correct.

3. **Conclusion**: Based on the analysis, the animal in which the tympanum is absent is the snake.

### Final Answer:
The correct answer is **Option 4: Snake**.

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