In countries nearer to polar region, the roads are sprinkled with `CaCl_2`. This is

Options

A. to minimise the snow fall
B. to minimise pollution
C. to minimise the accumulation of dust on the road
D. to minimise the wear and tear of the roads

Explanation

**Step-by-Step Solution:**

1. **Understanding the Problem:**
- In polar regions, heavy snowfall can block roads and make travel difficult.

2. **Role of Calcium Chloride (CaCl2):**
- Calcium chloride (CaCl2) is a non-volatile solute that is used to manage snow and ice on roads.

3. **Freezing Point Depression:**
- When CaCl2 is sprinkled on the roads, it dissolves in the water (from melted snow or ice) and lowers the freezing point of the solution. This phenomenon is known as freezing point depression.

4. **Melting of Ice:**
- The addition of CaCl2 causes the ice and snow on the roads to melt. This is because the freezing point of the water is lowered, allowing the ice to transition to liquid water even at lower temperatures.

5. **Resulting Effect:**
- As the ice melts, the snow is converted to liquid water, which helps to clear the roads and prevent blockage, making travel easier.

6. **Conclusion:**
- Therefore, the reason for sprinkling CaCl2 on roads in polar regions is to reduce the freezing point of water, thereby melting the snow and ice and facilitating smoother travel.

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