The Mettur Dam is an important source of:

Hydropower
Thermal power
Solar energy
Wind power

The correct answer is: a) Hydropower.

Hydropower is a form of energy that harnesses the power of moving water. It is a renewable energy source that can be used to generate electricity, provide water for irrigation and drinking, and control flooding.

The Mettur Dam is a large dam located on the Kaveri River in Tamil Nadu, India. It was built in 1934 and is one of the largest dams in India. The dam provides water for irrigation, drinking, and industrial use. It also generates electricity.

Thermal power is a form of energy that is generated by burning fossil fuels such as coal, oil, or natural gas. It is a non-renewable energy source that contributes to climate change.

Solar energy is a form of energy that comes from the sun. It is a renewable energy source that can be used to generate electricity, heat water, and power vehicles.

Wind power is a form of energy that comes from the wind. It is a renewable energy source that can be used to generate electricity.

I hope this helps!