Which of the following group of animals is homeothermal, has single occipital condyle, 12 pairs of cranial nerves, penumatic bones, and four- chambered heart ?

Options

A. Amphibia
B. Aves
C. Reptilia
D. Mammalia

Answer

To solve the question regarding which group of animals is homeothermal, has a single occipital condyle, 12 pairs of cranial nerves, pneumatic bones, and a four-chambered heart, we can follow these steps:

### Step 1: Understand the Characteristics
- **Homeothermal**: This term refers to animals that are warm-blooded and can maintain a stable internal body temperature regardless of external conditions. This is typically seen in birds and mammals.

### Step 2: Identify the Occipital Condyle
- **Single Occipital Condyle**: This is a feature found in certain vertebrates, including birds and mammals. It allows for greater head movement.

### Step 3: Count the Cranial Nerves
- **12 Pairs of Cranial Nerves**: This is a characteristic of mammals and birds. Other groups, like reptiles, have fewer pairs.

### Step 4: Recognize Pneumatic Bones
- **Pneumatic Bones**: These are bones that contain air spaces, which reduce weight and are commonly found in birds. They help in flight by making the skeleton lighter.

### Step 5: Identify the Heart Structure
- **Four-Chambered Heart**: This type of heart is found in birds and mammals, allowing for efficient separation of oxygenated and deoxygenated blood.

### Step 6: Compile the Information
- Based on the characteristics provided (homeothermal, single occipital condyle, 12 pairs of cranial nerves, pneumatic bones, and a four-chambered heart), the group of animals that fits all these criteria is **birds** (specifically, birds like apes).

### Conclusion
The correct answer to the question is **birds**.

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