Many a online shopper stayed up until 2 am on Sunday, looking through the Internet to buy products being sold at half price before they could _ (be bought)by other shoppers. Tens of millions of the Internet users were crazy to take advantage of the halfprice promotion, started by the ecommerce  giant Alibaba Group on Sunday, Nov. 11, which is known as Singles' Day in China, and is the Chinese answer to Cyber Monday in the United States. By 7 pm on Sunday, 14.1 billion yuan's worth of sales was made on tmall. com and taobao. com. That could make Singles' Day the biggest ecommerce sales day on record. The research company comScore said US online retailers   saw $ 1.25 billion of sales during last year's Cyber Monday, the day after Thanksgiving weekend and the busiest day for online retailers as US shoppers start to prepare for Christmas. Singles' Day originated with university students, and was later adopted by ecommerce companies as a promotional opportunity. Ecommerce companies, including Jingdong Mall and Amazon China, also took part in the promotion." In the past, people only shopped online occasionally, but now, online shopping is a lifestyle accepted by many," said Zhang Yong, Tmall president. Alibaba began to hold Singles' Day promotions in 2009, and last year, its sales totaled 5.2 billion yuan."I don't know whether we would lose money, but I don't think we could earn much on this day by selling goods at half price," said Hao Hongfeng, chairman of Beijing Jiuxian ECommerce, a liquor retailer in Beijing who took part in the event. He said it is a good opportunity for online retailers to get their names known. What's the secret behind the success of this promotion?
The quality of the products. The fame of the retailers. The favorable price. The aftersales service.
Question: Many a online shopper stayed up until 2 am on Sunday, looking through the Internet to buy products being sold at half price before they could _ (be bought)by other shoppers. Tens of millions of the Internet users were crazy to take advantage of the halfprice promotion, started by the ecommerce  giant Alibaba Group on Sunday, Nov. 11, which is known as Singles' Day in China, and is the Chinese answer to Cyber Monday in the United States. By 7 pm on Sunday, 14.1 billion yuan's worth of sales was made on tmall. com and taobao. com. That could make Singles' Day the biggest ecommerce sales day on record. The research company comScore said US online retailers   saw $ 1.25 billion of sales during last year's Cyber Monday, the day after Thanksgiving weekend and the busiest day for online retailers as US shoppers start to prepare for Christmas. Singles' Day originated with university students, and was later adopted by ecommerce companies as a promotional opportunity. Ecommerce companies, including Jingdong Mall and Amazon China, also took part in the promotion." In the past, people only shopped online occasionally, but now, online shopping is a lifestyle accepted by many," said Zhang Yong, Tmall president. Alibaba began to hold Singles' Day promotions in 2009, and last year, its sales totaled 5.2 billion yuan."I don't know whether we would lose money, but I don't think we could earn much on this day by selling goods at half price," said Hao Hongfeng, chairman of Beijing Jiuxian ECommerce, a liquor retailer in Beijing who took part in the event. He said it is a good opportunity for online retailers to get their names known. What's the secret behind the success of this promotion?
A. The quality of the products.
B. The fame of the retailers.
C. The favorable price.
D. The aftersales service.
Answer: