Artificial smoke screens are made by:

Options

A. `AI_(2)O_(3)`
B. PbO
C. `Na_(2)O`
D. `TiO_(2)`

Answer

**Step-by-Step Solution:**

1. **Understanding the Purpose of Artificial Smoke Screens:**
- Artificial smoke screens are primarily used in military operations. Their main purpose is to create a diversion for the enemy, making it difficult for them to see the movements or positions of military personnel.

2. **Formation of Smoke Screens:**
- These smoke screens are created by dispersing certain materials into the air, which then form a cloud-like barrier. This barrier obscures visibility and can help protect troops or equipment from enemy fire.

3. **Material Used for Smoke Screens:**
- The primary material used to create these artificial smoke screens is titanium oxide. This compound is effective in generating dense smoke when dispersed in the air.

4. **Conclusion:**
- Therefore, artificial smoke screens are made by using titanium oxide to create a visual barrier that serves as a tactical advantage in military operations.

**Final Answer:**
Artificial smoke screens are made by titanium oxide.

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