Question

Greenhouse effect is due to

Answer 1

Infrared rays
Infrared radiation is the part of the sunlight spectrum which causes the heating of the Earth’s surface. It has comparatively higher wavelength than X-rays and UV rays.
The greenhouse effect is the phenomenon of heating the Earth’s surface due to the absorption of heat, radiated back by the heated Earth’s surface, by the greenhouse gases such as CO2 followed by their emission towards the Earth’s surface, thus, avoiding their escape into space.

Final answer
(D) Infra-red rays