第30题: [单项选择]The end of the bidding is called "knocking down" because ______. A. the auctioneer knocks on the table B. the auctioneer names the highest bidder as the buyer of the goods C. the goods are knocked down onto the table D. the auctioneer bangs the table with a hammer 参考答案:D 答案解析:第一段最后一句表明这是因为拍卖帅用锤子击打讲台。