The average concentration of ____ has risen by approximately 40% between 1880 and 2012.
A) carbon monoxide
B) sulfur dioxide
C) ozone
D) carbon dioxide
E) nitrous oxide

Question

The average concentration of ____ has risen by approximately 40% between 1880 and 2012.​
A) ​carbon monoxide
B) ​sulfur dioxide
C) ​ozone
D) ​carbon dioxide
E) ​nitrous oxide

Quizplus · Accepted Answer

Carbon dioxide is the most likely option as it is a well-known greenhouse gas and its concentration has risen due to human activities such as burning fossil fuels. The other options are not as significant when it comes to climate change and their concentrations have not risen by as much.

The Average Concentration of ____ Has Risen by Approximately 40