题干

A、B、C、D均为中学化学中的常见物质且均含有同一种元素,它们之间的转化关系如图所示(反应条件及其他物质已经略去):

A +O2 B +O2 C +H2O D

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阅读下面材料,从每题所给的A、B、C、D四个选项中选出最佳选项。

D

    Do you have a lucky number? What is it? Many people have a special number. They hope it will bring them good luck.

    In Chinese culture, people believe some numbers are lucky or unlucky. This is based on the Chinese word that the number sounds similar to. 

    For example, the Chinese word for the number 8 sounds like the word for "making a fortune". So, people consider it a very lucky number. Some people spend a lot of money to have 8s in their phone numbers or vehicle license plate (车牌照) numbers. The opening ceremony of the Beijing Olympics began at 8:08 pm on August 8, 2008.

    The number 9 is also a lucky number because of its connection to the emperors (皇帝) of China. There were nine dragons on emperors' robes (龙袍). Today, 9 often stands for "long lasting". That's why a man always proposes to (向…求婚) a woman with 99 or 999 roses.

    So what's a "bad luck" number in China? It might be 4. Many Chinese people see 4 as a "bad luck" number because it sounds similar to the character for "death".

    Because of this, many buildings skip the fourth floor, and simply call it the fifth floor. In Hong Kong, some buildings even skip all floors numbered with 4, such as, 4, 14, 24, 34 all 40-49 floors. Some buildings also skip the 13th floor, as 13 is an unlucky number in the West. As a result, a building whose highest floor is 50 may actually have only 35 floors.