Nitrogen a. is the process where nitrogen is converted to a usable form. b. is accomplished by plants when they break down soil. c. occurs as a result of photosynthesis. d. none of the above.

the chemical processes by which atmospheric nitrogen is assimilated into organic compounds, especially by certain microorganisms as part of the nitrogen cycle. Hope this helps :)

b

Explanation:

the answer is lactic acid from anaerobic respiration. the acid in lactic acid is what creates sore and burning muscles. if you think about how acid burns that will give you a clue for questions like this.