Permanently 'open' or functional eyes are found in

Options

A. Snakes
B. Lizards
C. Crocodiles
D. Testudians

Answer

To answer the question regarding which reptiles have permanently open or functional eyes, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about reptiles that have permanently open or functional eyes. This means we need to identify which reptiles do not have eyelids that can close.

2. **Identifying Reptiles**: The reptiles mentioned in the question are snakes, lizards, crocodiles, and a term that seems to be a typo (possibly "custodians" should refer to "tortoises" or another group).

3. **Analyzing Each Reptile**:
- **Snakes**: Snakes do not have eyelids. Instead, they have a protective scale called a spectacle or brille that covers their eyes. This means their eyes are always open and functional.
- **Lizards**: Lizards have eyelids that can close, so their eyes are not permanently open.
- **Crocodiles**: Crocodiles have eyelids and can close their eyes, so they do not have permanently open eyes.
- **Tortoises**: Tortoises also have eyelids and can close their eyes.

4. **Conclusion**: Based on the analysis, the only reptiles from the options provided that have permanently open or functional eyes are snakes.

5. **Final Answer**: The correct answer is **snakes**.