Answer:
A. to limit nonsmokers' exposure to second-hand smoke.
Step-by-step explanation:
Usually, public restaurants, offices, have separate areas for smokers, to prevent second-hand smokers. According to Centers for Disease Control and Prevention (CDC), second-hand smokers harm children and adults, so they assure that the only way to eliminate this is to eliminate the smoke, meaning, not having smokers near. CDC textually says: ''Since 1964, approximately 2,500,000 nonsmokers have died from health problems caused by exposure to secondhand smoke.''
So, in order to prevent this health problems and to assure non-smokers comfortability, public places tend to have separate areas for smokers.