Some Prokaryotic Organisms Use Nitrogen Fixation to Obtain Organic Nitrogen $\equiv$

Some prokaryotic organisms use nitrogen fixation to obtain organic nitrogen.Which of the following statements about nitrogen fixation is false?

A) Nitrogen fixation requires the breaking a N $\equiv$ N triple bond.
B) Nitrogen fixation evolved after anaerobic photosynthesis,but before aerobic respiration.
C) Nitrogen fixation can only occur in the presence of oxygen.
D) Nitrogen fixation evolved as a way to obtain organic nitrogen for production of proteins and nucleic acids.