___ helps in fat digestion.

Options

A. Bile
B. Saliva
C. Pancreatic juice
D. HCI

Explanation

### Step-by-Step Solution:

1. **Understanding Fat Digestion**: The digestion of fats involves breaking down large fat molecules into smaller components, primarily fatty acids. This process is crucial for the body to utilize fats for energy and other functions.

2. **Emulsification of Fats**: The breakdown of fats is referred to as emulsification. This process converts fats into smaller globular forms, making them easier to digest.

3. **Role of Bile**: The main substance that aids in the emulsification of fats is bile. Bile is a digestive fluid that is essential for the digestion and absorption of fats.

4. **Source of Bile**: Bile is produced by the liver. After its production, bile is stored in the gallbladder until it is needed for digestion.

5. **Location of Fat Digestion**: The emulsification of fats primarily occurs in the duodenum, which is the first part of the small intestine. Bile is released into the duodenum to assist in fat digestion.

6. **Final Answer**: Therefore, the substance that helps in fat digestion is **bile**.