NO.PZ2020021203000067
问题如下：
Does it become more likely that a put option will be exercised before maturity when (a) the interest rate increases and (b) the stock price increases?
选项：
解释：
(a) When interest rates increase, the put option will be more likely to be exercised before maturity because the value of investing the profit at the risk-free rate after selling the stock at the strike price is increased. (b) When the stock price increases, the put option will be less likely to be exercised because the payoff from doing so will be smaller.
能不能提前行权不是取决于long方吗？但利率上升的时候，买方手中的钱在未来就更值钱了，所以等到行权日期再行权更划算，所以就不会希望提前行权。
