Colloidal gold is given by injection to act as

Options

A. Disinfectant
B. Anticancer agent
C. Germ killer
D. Tonic to raise vitality of human system

Explanation

**Step-by-Step Solution:**

1. **Understanding Colloidal Gold**: Colloidal gold refers to a suspension of fine gold particles in a liquid. This suspension is stable and does not settle out, which is a characteristic of colloids.

2. **Purpose of Injection**: Colloidal gold is administered via injection primarily to act as a therapeutic agent. It is known for its potential health benefits, particularly in enhancing the immune system.

3. **Mechanism of Action**: The gold particles in colloidal gold are believed to interact with the body’s biological systems. They may help in boosting vitality and improving overall health by acting as a tonic.

4. **Applications**: Colloidal gold is used in various applications, including:
- Acting as a disinfectant.
- Serving as an anti-inflammatory agent.
- Functioning as a germicidal tonic to improve the body's resistance against diseases.

5. **Conclusion**: In summary, colloidal gold is given by injection to act as a disinfectant and an anti-inflammatory agent, enhancing the vitality and immune response of the human body.

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