Through which of the following ways does the Sun primarily transfer its heat energy to the Earth?

The energy from the sun is the major source of living for all the being on the earth surface. The transfer of this heat energy to earth from sun is done through solar radiation, thermal radiation, electromagnetic energy transmission and re-radiation. Solar radiation is caused through nuclear fusion reactions where as thermal radiation is caused through a form of light. Electromagnetic energy transmission includes several types of radiations like light, infrared radiation, x-rays and ultraviolet rays.