Part of bile useful in digestion is

Options

A. Bile pigments
B. Bile salts
C. Bile matrix
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding Bile Composition**: Bile is a digestive fluid produced by the liver and stored in the gallbladder. It consists of several components, including bile pigments, bile salts, and bile acids.

2. **Identifying the Key Component**: Among these components, bile salts are the most important for digestion. They play a crucial role in the digestive process.

3. **Role of Bile Salts in Digestion**: Bile salts are primarily responsible for the emulsification of fats. Emulsification is the process by which large fat globules are broken down into smaller droplets, making it easier for digestive enzymes to act on them.

4. **Fat Digestion Process**: Once emulsified, fats can be further broken down into fatty acids and glycerol by enzymes such as lipases. This breakdown is essential for the absorption of fats in the intestine.

5. **Absorption of Fat-Soluble Vitamins**: In addition to aiding in fat digestion, bile salts also facilitate the absorption of fat-soluble vitamins (A, D, E, and K). These vitamins require the presence of bile salts for their absorption in the intestines.

6. **Conclusion**: Therefore, the part of bile that is most useful in digestion is the bile salts.

**Final Answer**: Bile salts.

---