Which two distinct microbial processes release dinitrogen `(N_(2))` from fixed nitrogen?
A. Decompose of organic nitrogen, conversion of dinitrogen to ammonium compounds
B. Enteric fermentation in cattle and nitrogen-fixation by Rhizobium in root nodules of legumes
C. Anaerobic ammonium oxidation and denitrification
D. Aerobic nitrate oxidation and nitrite reduction