Identify the mismatch among the following.

Options

A. Reptiles - Cleidoic eggs
B. Amphibians- Epidermal scales
C. Mammals - Corpus callosum
D. Aves - Pneumatic bones

Answer

To identify the mismatch among the given options, we will analyze each option step by step.

### Step 1: Analyze Reptiles with Chelidoic Eggs
- Chelidoic eggs are characterized by having protective shells and are adapted to prevent desiccation (drying out).
- This type of egg is indeed found in reptiles, making this option correct.

### Step 2: Analyze Amphibians with Epidermal Scales
- Epidermal scales are tough, keratinized structures found in reptiles, not amphibians.
- Amphibians typically have moist skin and do not possess scales like reptiles.
- Therefore, this option is incorrect, indicating a mismatch.

### Step 3: Analyze Mammals with Corpus Callosum
- The corpus callosum is a thick band of nerve fibers that connects the left and right cerebral hemispheres in mammals.
- This is a correct association, as all mammals have a corpus callosum.

### Step 4: Analyze Apes with Pneumatic Bones
- Pneumatic bones are hollow bones that contain air spaces, primarily found in birds to reduce weight for flight.
- While some apes may have lighter bones, they do not possess true pneumatic bones like birds.
- This option is also correct in the context of birds, but not specifically applicable to apes.

### Conclusion
From the analysis, the mismatch is found in the option regarding amphibians having epidermal scales, as amphibians do not have these structures.

### Final Answer
The mismatch is: **Amphibians having epidermal scales.**

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