【正确答案】 C

【答案解析】[听力原文]
   The price of gold fell to its lowest level in five years in trading early Monday. For a time, gold was selling at less than 1 100 dollars an ounce on Asian markets. Some traders are calling the price drop a "mini flash crash."
   Thirty billion dollars in short selling took place within half an hour during what are known as "stop-loss" sell-offs. Traders executed sell orders when gold prices reached targets set by investors. The sales manager of a Singapore business that sells gold and other precious metals says, "In the physical market, this would not be possible because that would consume a whole lot of physical gold. But in the futures market, because it's all digital as long as you find a buyer to bid for it, then that would be possible."
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