Question

which stage of the nitrogen cycle does the arrow in the image represent? choose 1 answer: a nitrogen fixation, in which nitrogen gas is converted into ammonia. b denitrification, in which nitrate is converted to nitrogen gas and returned to the atmosphere. c nitrification, in which ammonia is oxidized to nitrite and eventually nitrate. d ammonification, in which organic nitrogen is converted into ammonia or ammonium.

Explanation:

Nitrogen fixation is the conversion of nitrogen gas ($N_2$) into ammonia ($NH_3$). Denitrification is the conversion of nitrate ($NO_3^-$) to nitrogen gas. Nitrification is the oxidation of ammonia to nitrite and then nitrate. Ammonification is the conversion of organic - nitrogen to ammonia or ammonium. Without seeing the image, we can only explain the definitions of each process.

Answer:

No image is provided to determine the correct answer. Please provide the image for a proper response.