Answer : Atmosphere.
Explanation : The combination of gases that surrounds and protects the earth is known as Atmosphere.
An atmosphere is defined as a layer or a set of multiple layers of gases surrounding a planet or other material body, which is held in place by the gravity of that body.
It acts as an envelope of air around the earth and protects the earth from the harmful ultraviolet rays coming from the sun. Air in the atmosphere contains high amount of nitrogen which is 78.09 percent, oxygen is 20.95 percent, argon is 0.9 percent argon, carbon dioxide is 0.04 percent there is also small amounts of other gases.