最近的一项研究发现，每天喝两杯以上咖啡的从事久坐工作的中年男子比其他从事久坐工作的中年男子更可能血液胆固醇含量高，而胆固醇是患心脏病可能性增加的一个因素。胆固醇能够由饮食进入血液，但咖啡中不含有胆固醇。
下面哪个如果正确，最严重削弱了该研究的一个结论：咖啡增加从事久坐工作的中年男子得心脏病的危险
A．久坐的生活方式增加血液中的胆固醇含量。
B．咖啡里含有咖啡因，而咖啡因刺激心跳加快。
C．被观察者喝的咖啡中没有加含有胆固醇的奶或奶油。
D．在两组人之中的男人可能有些超重，而多余的体重又是增加心脏病可能的因素。
E．每日喝两杯以上咖啡的男人还吃更多胆固醇含量高的食品。
参考答案：E
解析：论证认为尽管“咖啡中不含有胆固醇”，但由于“每天喝两杯以上咖啡的从事久坐工作的中年男子血液胆固醇含量更高”，于是将“咖啡加从事久坐工作”作为“胆固醇增加的原因”。E选项说明“胆固醇增加的原因”是由于“吃更多胆固醇含量高的食品”，典型的他因削弱。
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| My husband had just bought a new washing machine for me. I decided to use it the 1 day, and I washed a lot of things. Everything worked 2 , but I could not find 3 of my husband's socks though I had looked 4 for it. The next morning, I got ready for 5 as usual. When the bell rang, the students came in. I greeted them and told them 6 we were going to do 7 . When I turned 8 to write on the blackboard, the class burst out 9 . They laughed so much, in fact, that I was 10 the headmaster would be in to see all this. I asked the class to 11 , but the 12 I talked, the more they laughed. So I thought I had better pay 13 attention to them and continue to write on the blackboard. When I did this, they laughed even more. Before long, the teacher who had the room next to 14 came to see 15 all the laughter was about. When he came in, he started 16 too. "Good Heavens!" I said."Will 17 please tell me what is so 18 ?" "Oh, God." Said the teacher."You have a brown 19 stuck to the back of your shirt." So that's 20 I found my husband's missing sock."Oh, well," I said to the class,"Let's just say you have had an unforgettable lesson on static electricity (静电)." | ||||
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