Which of the following structures is homologus to the wing of a bird?

Options

A. Wing of a moth
B. Hind limb of rabbit
C. Flipper of whale
D. Dorsal fin of a shark

Explanation

To determine which structure is homologous to the wing of a bird, we need to understand the concept of homologous structures and analyze the given options. Here’s a step-by-step solution:

### Step-by-Step Solution:

1. **Understand Homologous Structures**:
- Homologous structures are anatomical features in different species that share a common ancestry but may serve different functions. They arise from divergent evolution, where related species evolve different traits due to different environmental pressures.

2. **Identify the Wing of a Bird**:
- The wing of a bird is a modified forelimb. It is important to recognize that it has a specific structure and function related to flight.

3. **Evaluate the Options**:
- We need to look at the options provided and identify which one has a similar anatomical structure and common origin with the bird's wing.

4. **Analyze Each Option**:
- **Option A: Wing of a Moth** - This is not homologous because moths and birds do not share a common ancestor for their wings; they evolved independently for flight (convergent evolution).
- **Option B: Hind Limb of a Mammal** - This is a different structure altogether, as it is not a forelimb and does not share the same origin as the wing of a bird.
- **Option C: Flipper of a Whale** - This is a modified forelimb of a mammal. Both the wing of a bird and the flipper of a whale share a common origin as forelimbs of vertebrates, despite their different functions (flight vs. swimming).
- **Option D: Dorsal Fin of a Shark** - This is not homologous to the wing of a bird as sharks are fish and do not have forelimbs; their fins evolved separately.

5. **Conclusion**:
- The correct answer is **Option C: Flipper of a Whale**. Both the wing of a bird and the flipper of a whale are homologous structures because they share a common evolutionary origin and have similar anatomical features, even though they serve different functions.