NO.PZ2018062007000036
问题如下：
At expiration, the value of a European put option is
选项：
A.Max(0, ST-X)
B.Max(0, X-ST)
C.the underlying price
解释：
B is correct.
The exercise value of a European put option is the greater of zero or the exercise price minus the value of the underlying.
中文解析：
如果执行价格大于到期时标的资产价格，那么欧式看跌期权的exercise value = X-ST，否则exercise value = 0。即value=Max（0,X-ST）
欧式看跌期权的价值与无风险收益率为什么是负相关的呢？
