Presence of gills in the tadpole of frog indicates that `:`

Options

A. Fishes were amphibious in the past
B. Fishes evolved from frog like ancestors
C. Frogs will have gills in future.
D. Frogs evolved from gilled ancestors.

Answer

**Step-by-Step Solution:**

1. **Understanding the Life Cycle of Frogs**:
- Frogs undergo a metamorphosis from egg to tadpole and then to adult frog. The tadpole stage is aquatic and has gills for respiration.

2. **Identifying the Respiratory Structures**:
- Tadpoles have gills, which are specialized structures for breathing in water. Adult frogs, on the other hand, primarily use lungs and their skin for respiration.

3. **Comparing Tadpoles and Fish**:
- Both tadpoles and fish possess gills, indicating a similarity in their respiratory adaptations for aquatic life.

4. **Inferring Evolutionary Relationships**:
- The presence of gills in tadpoles suggests that frogs share a common ancestry with fish. This implies that frogs evolved from ancestors that had gills, which are typically found in fish.

5. **Evaluating the Options**:
- Given the options:
1. Fishes were amphibious in the past.
2. Fishes evolved from frog-like ancestors.
3. Frogs will have gills in the future.
4. Frogs evolved from gilled ancestors.
- The most accurate statement based on the presence of gills in tadpoles is that frogs evolved from gilled ancestors (fish).

6. **Conclusion**:
- Therefore, the correct answer is that the presence of gills in the tadpole of a frog indicates that frogs evolved from gilled ancestors.

**Final Answer**: Frogs evolved from gilled ancestors.

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