单选题 Which of the following is an example of an arbitrage opportunity?

A、 A portfolio of two securities that will produce a certain return that is greater than the riskfree rate of interest.
B、 A stock with the same price as another has a higher rate of return.
C、 A stock with the same price as another has a higher expected rate of return.

【正确答案】 A

【答案解析】An arbitrage opportunity exists when a combination of two securities will produce a certain payoff in the future that produces a return that is greater than the risk-free rate of interest. Borrowing at the riskless rate to purchase the position will produce a certain future amount greater than the amount required to repay the loan.