Question

Why does a smoker often cough

Answer 1

The answer is most likely a

Answer 2

The answer is c. Tar sticks to the cilia
When a smoker inhales these substances, the body tries to protect itself by coughing. The well-known "early morning" cough of smokers happens for a different reason. Normally, cilia (tiny hairlike formations lining the airways) beat outward and sweep harmful material out of the lungs.