Matte is obtained after this step-

Options

A. Froth floatation
B. Roasting
C. Smelting
D. Refining

Explanation

To determine after which step matte is obtained in the metallurgy of copper, we need to analyze the processes involved in extracting copper from its ore. The options given are flotation, roasting, smelting, and refining.

**Step 1: Understand the processes involved in metallurgy.**
- **Flotation**: This is a process used to separate the ore from the gangue (waste material) based on differences in their hydrophobic properties. It is typically the first step in the extraction of metals from their ores.
- **Roasting**: This process involves heating the ore in the presence of oxygen, which converts sulfide ores into oxides. For copper, this would convert copper(I) sulfide (Cu₂S) into copper oxides.
- **Smelting**: This is the process where the roasted ore is further heated, often in a furnace, along with a flux (like silica) to separate the metal from its oxide. In this step, the copper oxides are reduced to form copper metal and other by-products.
- **Refining**: This is the final step where the metal obtained is purified to remove impurities.

**Step 2: Identify the step where matte is produced.**
- The matte, specifically copper matte, is produced during the smelting process. During smelting, the copper(I) sulfide (Cu₂S) reacts with oxygen to form copper(I) oxide (Cu₂O) and sulfur dioxide (SO₂). The remaining copper(I) sulfide that does not convert to oxide forms a mixture known as copper matte, which contains copper and iron sulfides.

**Step 3: Conclusion**
- Therefore, the correct answer to the question "Matte is obtained after this step" is **smelting**.

### Final Answer:
Matte is obtained after the **smelting** step.