NO.PZ2018062007000015
问题如下：
Which of the following is most likely to describe arbitrage?
选项：
A.It is difficult to arbitrage when trading costs are high.
B.arbitrage opportunities exist when the ability to buy and sell short the asset is low.
C.arbitrage can tell investors the intrinstic value of an asset.
解释：
A is correct.
Arbitrage opportunities exist when trading costs are low, and investors have high ability to buy and go short the asset.
C is incorrect because arbitrage cannot tell us the intrinstic value. Arbitrage is based on a relative valuation method, whereas intrinstic value is based on an absolute valuation method.
低交易成本的情况下更容易出现套利机会，A正确；
套利交易需要便利的做多和做空机制，B错误；
套利不会告诉投资者资产的内在价值，因为套利取决于多空双方的相对价值，C错误。
B选项的中文意思是：当买入或做空的能力很弱（也就是很难买入或卖空资产）时，市场存在套利机会。
这个是错误的。套利交易需要的是很便利的买入和卖出的机制，应该是很强的ability，而不是很弱的ability。
我的理解是很强的ability，套利行为增加，套利机会消失呀。
就是因为弱，没有套利行为，才导致存在套利机会
