单选题 An analyst does research about market efficiency. Which of the following statements least likely explains why a market mispricing may persist?
A. Arbitrage is encouraged to produce riskless profits.
B. A price discrepancy is insufficient large to leave the investor with a profit.
C. Short selling is limited or restricted.

【正确答案】 A

【答案解析】[解析] 套利交易是指一种能够获得无风险收益的交易，它促进了市场的有效性，减少了错误定价证券的存在。由于人们觉得利润空间太小而不愿意套利交易，就会导致错误定价的证券长期存在，例如投资者要考虑套利交易的交易成本和信息获得成本。卖空交易是指投资者卖出其本不拥有的证券，投资者从券商处借入证券并承诺在未来的某个时间归还，限制卖空交易会导致错误定价的证券长期存在。