Question

which process in the nitrogen cycle returns nitrogen gas to the atmosphere? assimilation denitrification nitrification nitrogen fixation

Explanation:

Denitrification is the process in the nitrogen - cycle where nitrate is converted into nitrogen gas and returned to the atmosphere. Assimilation is the uptake of nitrogen compounds by plants and animals. Nitrification is the conversion of ammonia to nitrites and then to nitrates. Nitrogen fixation is the conversion of atmospheric nitrogen gas to ammonia.

Answer:

B. Denitrification