阅读下面的短文，从短文后所给各项的四个选项(A、B、C、D)中选出能填入相应空白处的最佳选项。 Health experts have warned ( 1) many years that smoking can ( 2) to heart disease, cancer (癌症，肿瘤) and ( 3) medical problems. And officials say diseases caused directly ( 4) smoking kill at ( 5) 320,000 Americans each year. But smokers still find ( 6) difficult to stop. The tobacco industry ( 7) 40 million Americans continue to smoke. Every year the American Cancer Society ( 8) a national Non-smoking Day in an ( 9) to get people to give ( 10) cigarettes. On that day the officers from the Society will ( 11) advice on ( 12) to stop smoking. Smokers ( 13) can call a special telephone number to ( 14) recorded messages by doctors. Some businesses will ( 15) their workers candy (糖果) or chewing gum (口香糖) to help them to keep ( 16) smoking. Some companies are offering special gifts and prizes to ( 17) who sign an agreement to stop smoking. And Americans ( 18) do not smoke are being asked to help ( 19) one person who is smoking during the 24- ( 20) campaign (运动). 1.of since for against 2.get lead take another 3.like another other few 4.from with by in 5.all least first last 6.that this it them 7.speaks says talks tells 8.forms organize makes picks 9.intention (意图) order attempt experiment 10.out in up away 11.take make give propose 12.what where how why 13.also either still further 14.hear accept send leave 15.lend sell offer reward 16.from in up at 17.anyone someone people them 18.what they who themselves 19.just often nearly hardly 20.hour week day hours