[please help ty] {30 points} {brainliest} Choose the answer that describes the hierarchy among these three body regions.

A. The cephalic region is part of the facial region, and the facial region is part of the oral region.
B. The oral region is part of the facial region, and the facial region is part of the cephalic region.
C. The cephalic region is part of the facial region, and the facial region is part of the oral region.
D. The oral region is part of the cephalic region, and the cephalic region is part of the facial region.

The answer is A!!

Explanation:

Hope it helped

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.

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.