I would have to say the answer is C.
A is incorrect since hydrogen is not an air pollutant.
B is incorrect because ozone is most definitely one of the top.
And D has cyanide which is a chemical for suicide during wars.
Hope this helps!
False, injuries are spontaneous and can happen to anyone flexible or not. However I do not know the statistics behind flexibility effecting injuries.
Answer:
B. a substance that sends the immune system into action
Explanation:
Numerous people.... Diabetics who are experiencing nerve degeneration of the extremities (something called Diabetic Neuropathy). Another group would be the elderly, who do loose sensation as age progresses. And lastly those with some sort of paralysis or peripheral nerve damage.
<span>Hypothalamic–pituitary–adrenal axis
I'm not sure, so please check and notify me :)
Hope this helps xox :)</span>
