Explain why smoking has been prohibited in many public places.
The question is asking us to explain why smoking has been prohibited in many public places. This is because smoking is bad for health - it can lead to cancer, lung problems and some other illnesses. While people should be allowed to smoke if they are adult and aware of the risks, no one should be forced to inhale smoke in public - especially the children have to be protected from the smoke. Hence, in many public places smoking is prohibited.