The important gas which was absent during the origin of life on Earth:

The gas which was absent in the environment during the origin of life is

Name the process of origin of life on earth.

Which gas was absent in the atmosphere of primitive earth?

Which gas was absent in the atmosphere of primitive earth ?

The correct sequence of the of the substances appeared during the course of origin of life on earth was:

The correct sequence of the of the substances appeared during the course of origin of life on earth was:

Which of the following is the correct sequence of chemical substance produced during the origin of life on the earth