The correct answer is: B. hydro power plant
A hydro power plant is a type of power plant that uses the power of moving water to generate electricity. The water is typically collected in a reservoir behind a dam, and then released through a turbine. The turbine spins a generator, which produces electricity.
Hydro power plants are a very efficient way to generate electricity, and they have a number of advantages over other types of power plants. They are non-polluting, they do not produce greenhouse gases, and they are relatively low-cost to operate.
However, hydro power plants also have some disadvantages. They can have a negative impact on the environment, as they can disrupt the flow of rivers and streams. They can also be expensive to build and maintain.
Overall, hydro power plants are a clean and efficient way to generate electricity. They have a number of advantages over other types of power plants, but they also have some disadvantages.
The other options are incorrect for the following reasons:
- Nuclear power plants are not able to start instantly. They require a significant amount of time to warm up and reach their full power output.
- Diesel power plants can start instantly, but they are not as efficient as hydro power plants. They also produce more pollution.
- Both (B) and (C) is incorrect, as only hydro power plants can start instantly.