Scientist are trying to reduce the amount of carbon dioxide and methane into the atmosphere which statement explains what most likely happened it was all this efforts

These efforts will decrease the amount of heat that the atmosphere traps.

Explanation:

Both Carbon dioxide and methane are considered to be green house gases.

However, green house gases are known to cause climatic changes by trapping or absorbing heat from the sun or in some other cases, produces large amount of heat through combustion, the result which can give rise to respiratory disease from smog and air pollution.

Hence, when Scientist tried to reduce the amount of carbon dioxide and methane into the atmosphere their efforts will decrease the amount of heat that the atmosphere traps.