Birds differ from reptiles in which one of the following character:-

Options

A. Skin has scales
B. They lay eggs
C. There are vertebrates
D. There is regulation of body temperature

Answer

To determine how birds differ from reptiles, we need to analyze the given options one by one.

### Step-by-Step Solution:

1. **Option 1: Skin has scales**
- Birds have scaly feet, and reptiles have scales covering their bodies. Thus, both birds and reptiles share this characteristic.
- **Conclusion**: This option is incorrect as it does not differentiate birds from reptiles.

2. **Option 2: Oviparous**
- Both birds and reptiles lay eggs, meaning they are both oviparous.
- **Conclusion**: This option is also incorrect since it does not provide a distinguishing feature.

3. **Option 3: Vertebrates**
- Both birds and reptiles belong to the subphylum Vertebrata, which means they are both vertebrates.
- **Conclusion**: This option is incorrect as it does not differentiate between the two groups.

4. **Option 4: Regulation of body temperature**
- Birds are warm-blooded (endothermic) animals, meaning they can regulate and maintain a constant internal body temperature. In contrast, reptiles are cold-blooded (ectothermic) and cannot internally regulate their body temperature.
- **Conclusion**: This option is correct as it highlights a key difference between birds and reptiles.

### Final Answer:
Birds differ from reptiles in the regulation of body temperature (Option 4).

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