Please answer the following question: Write a multi-choice question for the following article, with the given choices and answer: Article: Ali is from a Middle Eastern country. He now stays in the USA. He smokes a lot of cigarettes every day. He has smoked for nine years. Ali says, " I tried to quit smoking in my hometown, but it was impossible. My brothers smoke. All my friends smoke. At parties and at meetings, almost all the men smoke. Here in the United States, not as many people smoke. It will be easier to change my habit here." Many smokers are like Ali: they want to stop smoking. The smokers know that smoking is bad for their health. They know it can cause cancer and heart disease. But it is difficult for them to give up smoking because cigarettes have a drug in them. The drug is nicotine . People who smoke a lot need nicotine. When a person first begins to smoke, he usually feels terrible. The nicotine makes him sick. In a few days, the smoker's body is used to the nicotine, and he feels fine. Later, the smoker needs nicotine to keep feeling fine. Without nicotine, he feels bad. It is very hard to quit smoking, and many people who quit will soon smoke again. At a party or at work they will decide to smoke "just one" cigarette. Then they will smoke another cigarette, and another. Soon they become smokers again. Maybe there is only one easy way to quit smoking: never start. Options: A want to go to parties B can't smoke at work C know that smoking is bad for their health. D need nicotine and drugs Answer: C know that smoking is bad for their health. Question:
A:
Many smokers want to stop smoking because they _ .