Which of the following were the main gases in the initial atmosphere of Protoearth?
[A]Hydrogen and Helium
[B]Nitrogen and Carbon Dioxide
[C]Hydrogen and Nitrogen
[D]Oxygen and Carbon dioxide

Hydrogen and Helium
Protoearth, more massive and larger than Earth today, was molten and homogenous. The initial atmosphere, composed mostly of hydrogen and helium, was later driven off into space by intense solar radiation.