Due to which of the following the milk has white colour?

Options

A. Ceratine
B. Renin
C. Lactose
D. Casein

Explanation

**Step-by-Step Solution:**

1. **Understanding Milk Composition**: Milk is a complex liquid that contains various components, including proteins, fats, carbohydrates, vitamins, and minerals. The color of milk can be influenced by these components.

2. **Identifying the Options**: The question provides four options: keratin, vanine, lactose, and casein. We need to determine which of these contributes to the white color of milk.

3. **Analyzing Each Option**:
- **Keratin**: This is a protein found in hair, nails, and skin, not in milk. It does not contribute to the color of milk.
- **Vanine**: This is not a recognized component of milk. It seems to be a misspelling or confusion with "vanillin," which is related to flavor, not color.
- **Lactose**: This is the sugar found in milk. While it is a significant component, it does not contribute to the white color.
- **Casein**: This is a major protein found in milk, making up about 80% of the protein content. Casein is known to be an amorphous white solid, which contributes significantly to the white color of milk.

4. **Conclusion**: Based on the analysis, the correct answer is **casein**. It is the protein that gives milk its characteristic white color.

**Final Answer**: Casein is responsible for the white color of milk.

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