Pavlov is famous for his poineer work on

Options

A. Double circulation
B. Treatment of rabies
C. Mutation in primrose
D. Conditioned reflex in dog

Answer

**Step-by-Step Solution:**

1. **Identify the Scientist**: The question asks about Pavlov, a well-known scientist. His full name is Ivan Pavlov.

2. **Understand His Field**: Pavlov was a Russian physiologist, which indicates that his work is related to biology and the study of living organisms.

3. **Recognize His Contribution**: Pavlov is best known for his discovery of classical conditioning, a fundamental concept in behavioral psychology.

4. **Describe the Experiment**: He conducted experiments with dogs, where he trained them to salivate in response to a stimulus (a metronome or buzzer) that was previously associated with food.

5. **Conclusion**: Based on his work with dogs and the concept of conditioned reflexes, the correct answer to the question is option D: "conditioned reflex in dog."

**Final Answer**: Pavlov is famous for his pioneer work on conditioned reflex in dog (Option D).

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