Choose the example of discontinous distribution

Options

A. Lung fishes
B. Egg lying mammals
C. Pouched mammals
D. All of these

Answer

To solve the question about examples of discontinuous distribution, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Discontinuous Distribution**:
- Discontinuous distribution refers to a geographical range where species are found in isolated patches rather than being spread continuously across a region. This often indicates that the species are rare or at risk of extinction.

2. **Analyze the Options**:
- The question provides several options, and we need to evaluate each one to determine if it fits the definition of discontinuous distribution.

3. **Evaluate Lung Fishes**:
- Lung fishes are known to have both gills and lungs, allowing them to survive in various aquatic environments. However, they are not widely distributed and are found in specific regions, making them an example of discontinuous distribution.

4. **Evaluate Egg-Laying Mammals**:
- Egg-laying mammals, such as the monotremes (e.g., platypus and echidna), are a small group within the mammal classification. Since they are rare and not widely distributed, they also fit the criteria for discontinuous distribution.

5. **Evaluate Pouched Mammals**:
- Pouched mammals, like kangaroos and koalas, have a unique reproductive strategy where the young are carried in a pouch. Although more common than the previous examples, the number of species with this characteristic is still limited, which can also indicate a discontinuous distribution.

6. **Conclusion**:
- After evaluating all the options, we find that all the given examples (lung fishes, egg-laying mammals, and pouched mammals) are indeed instances of discontinuous distribution. Therefore, the answer to the question is that all of these are examples of discontinuous distribution.

### Final Answer:
All of these (lung fishes, egg-laying mammals, and pouched mammals) are examples of discontinuous distribution.

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