Energy produced by hydel-power plant is

The correct option is "Non-polluting and renewable".

Here is the step-by-step explanation of why this option is correct:

1. Understanding Hydel-Power (Hydroelectric Energy):
Hydel-power plants generate electricity by utilizing the kinetic energy of flowing or falling water (typically from a dam built across a river) to turn turbines, which then drive generators.

2. Why it is Renewable:
The water cycle is a continuous, natural process driven by solar energy. Water evaporates, forms clouds, and returns to the Earth as rain or snow, refilling the rivers and reservoirs. Because the water source is naturally replenished and not depleted by usage, hydroelectricity is classified as a renewable energy source.

3. Why it is Non-polluting:
Unlike fossil fuel-based power plants (such as coal or natural gas), hydroelectric power generation does not involve burning fuel. Therefore, it does not release harmful greenhouse gases (like carbon dioxide), soot, or air pollutants during operation, making it a clean and non-polluting method of generating electricity.