How are salamanders different from snakes ?

Options

A. Ancestors of snakes but not salamanders were tetrapods
B. Salamanders reproduce on land but snakes do not
C. Snakes but not salamanders lay a shelled egg
D. Salamanders are carnivores, and snakes are herbivores

Explanation

### Step-by-Step Solution:

1. **Identify the Organisms**: Recognize that the two organisms in question are salamanders and snakes. Both belong to the animal kingdom but are from different classes.

2. **Reproductive Differences**:
- **Egg Structure**:
- Snakes can lay eggs that are either hard or soft depending on the species.
- Salamanders, on the other hand, always lay soft eggs.
- **Egg Shelled vs. Non-shelled**:
- Snake eggs are typically shelled, providing protection to the developing embryo.
- Salamander eggs are non-shelled, which means they are more vulnerable.

3. **Laying Habitats**:
- **Location of Egg Laying**:
- Snakes usually lay their eggs on land.
- Salamanders prefer to lay their eggs in moist environments, often in water.

4. **Conclusion**: Based on the differences in egg structure, shelled versus non-shelled eggs, and the habitats where they lay their eggs, we can conclude that snakes and salamanders have significant reproductive differences.

5. **Correct Option**: From the options provided, the statement that "snakes but not salamanders lay a shelled egg" is true, making it the correct choice.