Which of the following show restricted distribution?

Options

A. Elephants
B. Pouched mammals
C. Alligators
D. Lung fishes

Answer

To determine which of the following shows restricted distribution, we need to analyze the distribution patterns of the given animals. Restricted distribution refers to species that are confined to a specific geographic area and cannot thrive outside of that area.

### Step-by-Step Solution:

1. **Understanding Restricted Distribution**:
- Restricted distribution means that a species is found only in a specific area and cannot survive in other regions.

2. **Analyzing Elephants**:
- Elephants are found in Africa and South Asia. They have a broad range and are not limited to a specific area. Therefore, they do not show restricted distribution.

3. **Analyzing Pouched Mammals**:
- Pouched mammals, such as kangaroos, are primarily found in Australia. They have a very specific distribution and cannot survive outside of this region. Thus, they show restricted distribution.

4. **Analyzing Alligators**:
- Alligators are found in a wide range of habitats, including the southeastern United States and parts of Canada. Their distribution is not limited to a specific area, indicating they do not have restricted distribution.

5. **Analyzing Lungfishes**:
- Lungfishes have a limited distribution, being found in South America and Africa. However, their range is broader than that of pouched mammals, so they do not qualify as having restricted distribution when compared to them.

6. **Conclusion**:
- Among the options given, pouched mammals are the only group that shows restricted distribution, as they are confined to Australia and cannot survive outside this region.

### Final Answer:
Pouched mammals show restricted distribution.