The correct answer is (c) Thermal power.
Thermal power is the largest source of electricity in India, accounting for 62.7% of total generation in 2020. Coal is the primary fuel used for thermal power generation, followed by natural gas and oil.
Hydro power is the second largest source of electricity in India, accounting for 13.4% of total generation in 2020. Hydro power plants use the energy of falling water to generate electricity.
Atomic power is the third largest source of electricity in India, accounting for 3.8% of total generation in 2020. Atomic power plants use the heat from nuclear fission to generate electricity.
All above have equal shares is the wrong answer because thermal power has the largest share in power generation in India, followed by hydro power and atomic power.