It is the mongols, this answer is
<span>Radon may cause lung cancer when inhaled.
a: is formed by the breakdown of the ozone layer
b: may cause lung cancer when inhaled
c: binds with hemoglobin, preventing binding with oxygen
d: contributes to the breakdown of the ozone layer
e: in the atmosphere limits the availability of sunlight for plants</span>
The answer is - it can not be taken out of the atmosphere.
The nitrogen, even though makes for about 78% of our atmosphere, and is by far the most abundant gas in it, we can not use it because it can not be taken out of the atmosphere as it is. If we take nitrogen in the form as it is in the atmosphere it is useless for both, humans and plants. It has to go through a process of ''fixation'' first before we can actually use it in our food.
It would be a formal region.
A its cites thanks your welcome