I think the answer would be b because your throat is reacting to the cough?
Answer:
The correct answer is option B
Explanation:

Given values,
Molarity of 
Volume of solution, 
Molecular weight of 
Substituting this values in Molarity formula, we get

CO2 ; H20- They are the only ones that, on both sides, combined with another element and bonding of atoms
Answer:
D) It has a different unit than atomic mass.
Can i get a list of possible answers plz?