Convergent evolution is illustrated by

Options

A. Rat and Dog
B. Bacterium and Protozoan
C. Starfish and Cuttle fish
D. Dogfish and Whale.

Answer

**Step-by-Step Solution:**

1. **Understanding Convergent Evolution**:
- Convergent evolution occurs when different species develop similar traits or adaptations due to similar environmental pressures, despite having different evolutionary ancestors.

2. **Identifying Examples of Convergent Evolution**:
- Look for pairs of organisms that have adapted to similar environments and exhibit similar morphological traits. Common examples include:
- Wings of bats, birds, and insects.
- Streamlined bodies of dolphins and whales.

3. **Analyzing the Given Options**:
- Review each option to determine if they illustrate convergent evolution:
- **Option A: Rat and Dog** - Different lineages, no similar morphology.
- **Option B: Bacterium and Protozoa** - Microorganisms with irregular shapes, no stable morphology.
- **Option C: Starfish and Cuttlefish** - Different body organizations due to different body symmetries.
- **Option D: Dogfish and Whales** - Both have streamlined bodies and similar body organization, indicating convergent evolution.

4. **Selecting the Correct Answer**:
- Based on the analysis, **Option D (Dogfish and Whales)** is the best example of convergent evolution as they share similar adaptations due to living in similar aquatic environments.

5. **Conclusion**:
- Convergent evolution is illustrated by organisms that, despite having different evolutionary backgrounds, develop similar traits due to analogous environmental pressures.

**Final Answer**: Convergent evolution is illustrated by Dogfish and Whales (Option D).

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