Out of the following, hydrophobicsol is:

Options

A. gum
B. starch
C. gelatin
D. sulfure

Explanation

To determine which of the given options is a hydrophobic sol, we need to understand the concept of hydrophobic and hydrophilic sols.

### Step-by-Step Solution:

1. **Define Hydrophobic Sol**:
- A hydrophobic sol is a colloidal solution that does not interact well with water. The term "hydrophobic" means "water-hating." These sols tend to repel water and do not dissolve in it.

2. **Identify the Options**:
- The options provided are: gum, starch, gelatin, and sulphur.

3. **Analyze Each Option**:
- **Gum**: This is a hydrophilic substance, meaning it interacts well with water and can dissolve in it.
- **Starch**: Starch is also hydrophilic. It is a carbohydrate that can absorb water and swell.
- **Gelatin**: Gelatin is another hydrophilic substance. It dissolves in warm water and forms a gel-like structure upon cooling.
- **Sulphur**: Sulphur is a non-metal and does not mix with water. It is considered hydrophobic.

4. **Conclusion**:
- Among the given options, sulphur is the only hydrophobic sol.

### Final Answer:
The hydrophobic sol out of the given options is **sulphur**.

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