Many animals, like mice, when they sense danger. run freeze eat hiss
1run
2feeze
3eat
4hiss

i wanna say run or freeze

explanation:

b,bacteria convert nitrates

into nitrogen gas.

d,plants and animals take in

and use nitrogen compounds.

e,bacteria break down waste    

products and return nitrogen  

to the soil.

a,bacteria convert atmospheric

nitrogen to ammonia.

c,bacteria convert ammonia

to nitrites and nitrates.

c is the answer to this question. altitude affects the weather because air molecules evaporate.