The extraction of metal from sulfide ore is done by

Options

A. electrolysis
B. smelting process
C. metal displacement
D. none of these

Explanation

### Step-by-Step Solution:

1. **Identify the Type of Ore**: The question specifies that we are dealing with sulfide ores. Sulfide ores contain metal combined with sulfur.

2. **Understand the Extraction Process**: The extraction of metals from sulfide ores is primarily done through a process known as smelting.

3. **Explain the Smelting Process**:
- In the smelting process, sulfide ores are heated in a blast furnace.
- During this heating, the sulfide is converted into an oxide. This step is crucial because metals are typically more easily extracted from their oxide forms than from their sulfide forms.

4. **Use of Reducing Agents**: After the sulfide is converted to an oxide, a suitable reducing agent is used to reduce the metal oxide back to its elemental form. Common reducing agents include carbon (in the form of coke) or other metals.

5. **Final Extraction**: The result of the smelting process is the extraction of the metal in its elemental form, which can then be further purified if necessary.

### Final Answer:
The extraction of metal from sulfide ore is done by the smelting process.

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