A liquid metal is

Options

A. copper
B. bromine
C. silver
D. mercury

Explanation

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for a liquid metal.

2. **Understand the Properties of Metals**: Metals are typically solid at room temperature, have a shiny appearance, are good conductors of heat and electricity, and can be malleable and ductile.

3. **Consider the Exceptions**: While most metals are solid, there are exceptions where metals can exist in a liquid state.

4. **Identify Liquid Metals**: The only metal that is liquid at room temperature is mercury, which has the chemical symbol Hg.

5. **Evaluate Other Options**:
- Copper is a metal but is solid.
- Bromine is a non-metal and is liquid, so it does not qualify as a liquid metal.
- Silver is also a metal but is solid.

6. **Conclude the Answer**: Therefore, the only liquid metal is mercury (Hg).

**Final Answer**: The liquid metal is mercury.

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