完形填空

先通读下面的短文，掌握其大意，然后在每小题所给的A、B、C、D四个选项中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。

Few people like changing their habits, good or bad. Whether it is smoking, drinking or over-eating, they 1“enjoying”them to the end.

On every packet of cigarettes(香烟), people are warned against the2of smoking: “Warning: Cigarette Smoking Is Dangerous to Your Health”.3, millions of them start smoking or go on smoking. Why?

Facts show that families and surroundings(环境) play a very important part in 4 smokers. All those smokers come from smoking families or have smoking5 or relatives. Films and TV plays also play a part. People6their “heroes" on TV drinking alcohol(酒) or smoking cigarettes. “Heroes” seem to fear7, neither killing themselves nor killing others with alcohol and cigarettes. If they are not afraid of the harm of smoking and drinking,8should common people be afraid?

The simple warning on the cigarette packet does not influence smokers' habits. Even 9warnings, like showing pictures of smokers who have died of cancer, don't seem to work.  

Knowing and believing seem to be two10 things. If smoking is really as harmful as doctors say, it is time for smokers to think about it and try to give it up!

材料一：艾森豪威尔政府（1953——1960年）显得更激烈地敌视北京。美国不仅拒绝承认中华人民共和国，还顽固地反对它加入联合国。美国推行了一项对中国实施军事包围的政策，其中包括美国在朝鲜、日本、冲绳、台湾、南越、缅甸和泰国等地区保持军事基地。

——徐中约《中国近代史：1600—2000中国的奋斗》

材料二：1971年7月6日，尼克松总统在美国堪萨斯城对世界格局提出了“五个中心”的看法。他认为，美、苏、中、西欧和日本是世界的五个力量中心。美国意识到自己的霸权地位已严重衰落，面对苏联的争霸，美国领导人更产生了紧迫感。正是在这样的背景下，作为全面执行尼克松主义的一项内容，为了改善在美苏争霸中美国的战略处境，美国开始了接近中国的过程。

——《中国外交史一一中华人民共和国时期》

材料三：尽管中国人说是尼克松政府急于要求得到北京之行的准许的，但是中国自己的动机却是掩盖不住的。基辛格秘密访华两周后，《红旗》杂志发表了一篇文章，最坦诚地公开讲述了对美开放的正当理由：竟不含糊地区分了两个超级大国对中国威胁的程度及其对北京安全考虑所产生的影响。

——（美）费正清《剑桥中华人民共和国史》

请回答：