(辨认主题句)Choose the best topic sentence from the four options below.Write the corresponding letter of your choice in the blank provided.
Your choice:
A
Passive smokers may easily catch the diseases active smokers invite.
B
Passive smoking is becoming widely recognized as a major health hazard.
C
Researchers find that second-hand smoke increases one’s risk of lung cancer.
E
Passive smoking refers to the second-hand smoke that nonsmokers breathe in.