Which one of following are analogous structure :-

Options

A. Wings of Bat and Wings of Pigeon.
B. Gills of Prawn and Lungs of Man.
C. Thorns of Bougainvillea and Tendrils of Cucurbita
D. Flippers of Dolphin and Legs of Horse

Answer

To determine which of the following options represents analogous structures, we need to first understand what analogous structures are.

### Step-by-Step Solution:

1. **Definition of Analogous Structures**:
- Analogous structures are biological features in different species that perform similar functions but do not share a common evolutionary origin. This means they evolved independently in different lineages.

2. **Examine the Options**:
- **Option A**: Wings of bat and wings of pigeon.
- Both are used for flying but share a common evolutionary origin as they are both derived from vertebrate ancestors. Thus, they are homologous structures, not analogous.

- **Option B**: Gills of prawn and lungs of man.
- Both structures serve the function of respiration. However, they come from different evolutionary origins (gills in aquatic organisms and lungs in terrestrial organisms). Therefore, they are analogous structures.

- **Option C**: Thorn of Bougainvillea and tendrils of Cucumber.
- These structures serve different functions (protection vs. support) and are not similar in function or origin, so they are not analogous.

- **Option D**: Flippers of dolphin and legs of horse.
- Both serve the function of locomotion but are derived from a common ancestor (the vertebrate limb), making them homologous structures, not analogous.

3. **Conclusion**:
- After analyzing all the options, the correct answer is **Option B**: Gills of prawn and lungs of man, as they are analogous structures.

### Final Answer:
**Option B: Gills of prawn and lungs of man.**

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