Snake lack

Options

A. Scales
B. Tympanum
C. Ribs
D. Locomation

Answer

To answer the question "Snakes lack," we will analyze each option provided and determine which one is correct.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks what snakes lack among the given options. We will evaluate each option to find out which one is not present in snakes.

2. **Evaluating Option A: Scales**:
- Snakes are reptiles and one of their characteristic features is the presence of scales.
- Therefore, snakes do **not lack** scales. This option is incorrect.

3. **Evaluating Option B: Tympanum**:
- The tympanum is the ear membrane. Snakes do not have external ears or tympanum membranes, which distinguishes them from some other reptiles like lizards.
- Therefore, snakes do lack tympanum. This option is correct.

4. **Evaluating Option C: Ribs**:
- Snakes have a well-developed skeletal system that includes ribs. These ribs protect internal organs and assist in respiration.
- Therefore, snakes do **not lack** ribs. This option is incorrect.

5. **Evaluating Option D: Locomotion**:
- Snakes are capable of locomotion despite being limbless. They can move by crawling and slithering.
- Therefore, snakes do **not lack** locomotion. This option is incorrect.

6. **Conclusion**: After evaluating all options, the only correct answer is that snakes lack the tympanum.

### Final Answer: Snakes lack tympanum.

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