Cinnabar is

Options

A. HgO
B. CuO
C. HgS
D. `Cu_(2)S`

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the identification of Cinnabar from the given options: HgO, CuO, HgS, or Cu2S.

2. **Researching Cinnabar**: Cinnabar is a naturally occurring mineral that is primarily composed of mercury sulfide.

3. **Identifying the Chemical Formula**: The chemical formula for Cinnabar is HgS, which stands for mercuric sulfide.

4. **Reviewing the Options**:
- HgO is mercuric oxide.
- CuO is cupric oxide.
- HgS is mercuric sulfide (Cinnabar).
- Cu2S is cuprous sulfide.

Among these, HgS is the correct answer.

5. **Conclusion**: Therefore, Cinnabar is identified as HgS.

**Final Answer**: Cinnabar is HgS (mercuric sulfide).

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