Question

1. volcanic outgassing aided in formation of the atmosphere by

pouring all the oxygen into the atmosphere
adding free hydrogen and oxygen into the atmosphere to eventually react to make water vapor
adding water vapor and carbon dioxide to the atmosphere
none of the above

Explanation:

Volcanic outgassing releases water vapor, carbon - dioxide, nitrogen and other gases into the atmosphere. It did not pour all oxygen into the atmosphere. Also, it didn't add free hydrogen and oxygen to form water vapor in the described way.

Answer:

C. adding water vapor and carbon dioxide to the atmosphere