Which of the Following Is Not an Example of "Fixing

Multiple Choice

Which of the following is not an example of "fixing" nitrogen?

A) Scientists combine dinitrogen and hydrogen gases to form ammonia.
B) Bacteria convert dinitrogen from the atmosphere into ammonium ion and nitrate ion containing compounds.
C) Denitrifying bacteria decompose organic compounds into dinitrogen gas.
D) When magnesium combusts in air,some magnesium also reacts with dinitrogen to produce magnesium nitride.
E) Lightning strikes in the atmosphere produce nitrogen monoxide from dinitrogen and dioxygen gases.