Which process describes nitrogen fixation?
question 19 options:

animals eat plants containing nitrogen and return it to the soil through urination

bacteria take nitrogen from the air and convert it to a form usable by plants

organisms die and are decomposed into ammonia in the soil

plants take nitrogen from the air and store it in their roots

bacteria take nitrogen from air and convert it to a form usable by plants

Bacteria take Nitrogen from air and convert it to a form usable by plants.

^w^

well for one plants are always the producer, so a is the answer. a wolf is more of the consumer(predator) and the deer is the prey so i know those two are out of the question. also mushrooms are fungi/fungus so a is the producer.

layer 3 is younger than layer 6.