What is secondhand smoke?
A) the smoke that enters your lungs when you inhale the smoke
B) the smoke that emanates from the end of a burning cigarette or pipe (sidestream smoke)
C) a combination of sidestream and mainstream smoke
D) the smoke that is exhaled from the lungs of smokers (mainstream smoke)
Question 2
Which of the following is a smoking-related disease that affects the mouth?
A) periodontal disease
B) emphysema
C) gastro-esophageal reflux
D) COPD