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问题 判断题

凡是列入强制性产品认证目录内的产品，必须经国家许可的认证机构认证合格，取得认证证书，并加施认证标志“CCC”标志后，方可出厂销售、进口和在经营性活动中使用。（）

答案

参考答案：对

填空题

（）是战国时的一部经典；这部书具有浓厚的浪漫主义色彩；“相濡以沫，不如相忘于江湖”是其中的名句；这部书中有一段经典的关于“安知鱼之乐”的辩论；这部书的作者是道家的代表之一。
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单项选择题

Potato cyst nematodes are a pest of potato crops. The nematodes can lie dormant for several years in their cysts, which are protective capsules, and do not emerge except in the presence of chemicals emitted by potato roots. A company that has identified the relevant chemicals is planning to market them to potato farmers to spread on their fields when no potatoes are planted; any nematodes that emerge will soon starve to death.
Which of the following, if true, best supports the claim that the company’s plan will be successful

A．Nematodes that have emerged from their cysts can be killed by ordinary pesticides.

B．The only part of a potato plant that a nematode eats is the roots.

C．Some bacteria commonly present in the roots of potatoes digest the chemicals that cause the nematodes to emerge from their cysts.

D．Trials have shown that spreading even minute quantities of the chemicals on potato fields caused nine-tenths of the nematodes present to emerge from their cysts.

E．(E) The chemicals that cause the nematodes to emerge from their cysts are not emitted all the time the potato plant is growing.
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