—Look! I found a wallet in the classroom

—You should give it to its        .He must be upset about losing it.

A．volunteer

B．nurse

C．passenger

D．owner

（）有权在某一确定的时间或确定的时间之内，以确定的价格购买相关资产。

A．美式期权的买方 

B．欧式期权的卖方 

C．看涨期权的买方 

D．看跌期权的卖方