The nitrogen utilized by most plants is derived from
a. decayed organic matter.
b. the atmosphere.
c. soil.
d. nitrogen gas.

The best answer is C. -  soil

The nitrogen used by most plants is derived from soil.

Nitrogen is an important element. It is needed by organisms to produce amino acids 

Nitrogen is made usable for plants by bacteria which change nitrogen to  ammonium.

Ammonium  gets changed to nitrates by bacteria in a process called nitrification, which takes place in soil.

Nitrates is the form that plants can absorb. They absorb it through their roots and use it to make amino acids, nucleic acid and chlorophyll.

stress fractures occur largely in the feet and legs and are common in sports that require repetitive impact, primarily running/jumping sports such as gymnastics or track and field.

a. decomposes use carbon from dead organisms as fuel for cellular respiration, returning carbon dioxide back into the atmosphere.