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!
Answer:
Diabetic foot ulcer
Explanation:
A diabetic foot ulcer is an open sore or wound that occurs in approximately 15 percent of patients with diabetes and is commonly located on the bottom of the foot.
Hope this helps you out : )
