Answer:
The correct answer is option A.
Explanation:
Percentage of nitrogen gas in an our atmosphere = 78%
Percentage of oxygen gas in an our atmosphere = 21 %
Percentage of other gases =100% - 78% - 21% = 1%
Our atmosphere is majorly constituted by nitrogen gas that 78 % and oxygen gas with 21 %. Remaining gases present in our atmosphere are present by 1%.