Distribution of clean and quality milk throughout the world has been made possible through work of

Options

A. Leeuwenhoek
B. Koch
C. Pasteur
D. Blackman

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about who contributed to the distribution of clean and quality milk worldwide.

2. **Identifying Key Terms**: The key term here is "pasteurization," which is a method used to ensure the safety and quality of milk.

3. **Defining Pasteurization**: Pasteurization is a process that involves heating milk to a specific temperature (usually below 100 degrees Celsius) to kill harmful microbes and extend the shelf life of the product.

4. **Identifying the Scientist**: The process of pasteurization was developed by Louis Pasteur. He is known for his work in microbiology and for creating this method to prevent spoilage in food products, including milk.

5. **Evaluating the Options**:
- **Leeuwenhoek**: Known as the father of microbiology, but did not develop pasteurization.
- **Koch**: Known for his postulates related to infectious diseases, not for pasteurization.
- **Pasteur**: Correct answer, as he developed the pasteurization process.
- **Blackman**: Known for his work on limiting factors in plants, unrelated to milk quality.

6. **Conclusion**: The correct answer is Louis Pasteur, as he was instrumental in the development of the pasteurization process that ensures the distribution of clean and quality milk.

### Final Answer:
The distribution of clean and quality milk throughout the world has been made possible through the work of **Louis Pasteur**.

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