为什么long interest rate put option可以hedge against rising interest rate? interest rate put option 是利率下降赚钱，利率上升没关系啊。利率上升，long interest call赚钱,所以long interest call 不是可以来hedge against rising interest rate吗？就像long call option可以帮short stock postion抵御股价上升带来的损失。
