题目
Which of the following has the same impact on both American call and put option prices? I.An increase in volatility. II.An increase in the stock price. III.An increase in the risk-free rate. IV.A decrease in time to expiration.
选项
A.I only.
B.I and II.
C.I and III.
D.I and IV.
答案
D
解析
Increased volatility positively influences put and call option values, while a decrease in time to expiration will negatively influence call and put prices. Note that an increase in the stock price and an increase in the risk-free rate will cause the price of an American call to increase but will cause the price of an American put to decrease.波动性的增加会对看跌期权和看涨期权的价值产生积极影响，而到期时间的缩短会对看跌期权和看涨期权的价格产生消极影响。请注意，股票价格的上升和无风险利率的上升将导致美式看涨期权的价格上升，但将导致美式看跌期权的价格下降。