NO.PZ2015122801000030
问题如下：
Which of the following statements is most correct?
选项：
A.When market price goes down, putable shares are more risky than callable shares for investors.
B.When market price goes up, callable shares are more risky than putable shares for investors.
C.When market price changes, non-putable, non-callable shares are the most risky for investors.
解释：
B is correct.
When market price rises, the firm has option to buy back the shares , therefore investors have limited gains when they hold the callable shares. When market price drops, investors can sell the shares back to the firm, therefore investors have protection when they hold the putable shares.
B是正确的。
本题考察可卖还，可赎回股票的区别。
当市场价格上升时，股票的发行方（公司）很可能会用固定价格强制买回股票，此时持有该种股票的投资者就可能无法获得股票进一步上涨的收益，面临的风险最大，所以B正确。
当市场价格下降时，投资者可以强制要求公司以约定的（可能高于市场价格）价格购回股票，则不用再承担股价下跌的风险，此时可卖回股票的投资者面对的风险时最小的。所以A错。
普通的股票，由于不含有赎回或是卖回的权利，不会被强制赎回或是强制发行方买回。所以对于市场价格的变动，风险都是相对居于中间的。C错误。
callable common share和putable common share不是看涨期权和看跌期权吗
