Match the methods of concentration of ore given in column-I with the different ores given in column-II and select the correct option.
column-I (I) magnetic separation (II) froth flotation (III) hydraulic washing column-II (a) `Cu_2S (b) Fe_3O_4 (c) Al_2(SiO_3)`

Options

A. I(a), II(b), III(c)
B. I(b), II(a), III(c)
C. I(c), II(a), III(b)
D. I(b), II(c), III(a)

Answer

To solve the problem of matching the methods of concentration of ore from Column-I with the different ores from Column-II, we will analyze each method and its corresponding ore step by step.

### Step 1: Analyze Magnetic Separation
- **Magnetic Separation** is a method used when either the ore or the impurities are magnetic in nature.
- In Column-II, we have `Fe3O4`, which is known as magnetite. Magnetite is magnetic.
- Therefore, the correct match for **Magnetic Separation** is **(b) Fe3O4**.

### Step 2: Analyze Froth Flotation
- **Froth Flotation** is a method used for the concentration of sulfide ores.
- In Column-II, we have `Cu2S`, which is the sulfide ore of copper.
- Therefore, the correct match for **Froth Flotation** is **(a) Cu2S**.

### Step 3: Analyze Hydraulic Washing
- **Hydraulic Washing** (also known as gravity separation) is used when the ore is heavy and the impurities are lighter.
- In Column-II, we have `Al2(SiO3)`, which is heavier than the impurities.
- Therefore, the correct match for **Hydraulic Washing** is **(c) Al2(SiO3)**.

### Final Matching
Now we can summarize the matches:
1. **Magnetic Separation** - (b) Fe3O4
2. **Froth Flotation** - (a) Cu2S
3. **Hydraulic Washing** - (c) Al2(SiO3)

Thus, the final answer is:
- (I) Magnetic Separation - (b) Fe3O4
- (II) Froth Flotation - (a) Cu2S
- (III) Hydraulic Washing - (c) Al2(SiO3)

### Correct Option
The correct option is the one that matches these pairs, which is **Option 2**.

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