问题如下图：
选项：
A. 
B. 
C. 
D. 
解释：
Buy a put against rising interest rates ，不应该是价格跌了会有利吗？为什么要against rising？不应该是against 利率下跌吗？
品职答疑小助手雍 · 2019年08月21日
同学你好，他买的应该是债券的期权，利率上升债券价格会下降，买债券的put防范债券价格下降的风险。
我们 · 2019年08月21日
那意思就说这里against的是价格下跌。所以担心价格下跌，就long put，在这个option里 ,越跌越赚钱？
品职答疑小助手雍 · 2019年08月21日
对啊，long put就是越跌越赚钱的~
我们 · 2019年08月21日
因为在课间中有讲到：interest rate cap，是long interest rate call，那这里因为是bond option，就是和课件上讲的相反？short call？
品职答疑小助手雍 · 2019年08月21日
直接买的债券的put，债券价格下跌了就赚钱，不用延伸那么多的~
我们 · 2019年08月21日
那考试时如何判断是买了bond put 还是 interest rate put？因为这两个结果是完全相反的啊
品职答疑小助手雍 · 2019年08月21日
他题目里描述了买一个put防止价格下跌就肯定是bond future啊
品职答疑小助手雍 · 2019年08月21日
说错，肯定是bond option。
我们 · 2019年08月22日
那如果没有提到bond，就是interest rate call 和 put吗？结果就是反向的，对吗
品职答疑小助手雍 · 2019年08月22日
这个真的可以通过题面判断出来的，不用纠结是不是需要自己猜它是bond还是interest的option。
NO.PZ2016082402000032 A portfolio manager wants to hee his bonportfolio against changes in interest rates. He inten to buy a put option with a strike pribelow the portfolio’s current priin orr to proteagainst rising interest rates. He also wants to sell a call option with a strike priabove the portfolio’s current priin orr to rethe cost of buying the put option. Whstrategy is the manager using? BespreStrangle Coll Strale ANSWER: C The manager is long a portfolio, whiis protectebuying a put with a low strike prianselling a call with a higher strike price. This locks in a range of profits anlosses anis a collar. If the strike prices were the same, the hee woulperfect. collar的图形是不是和bull sprea样？ 区别是sprea都用call 或者 都用put，coll要用一个call一个put？
Strangle Coll Strale ANSWER: C The manager is long a portfolio, whiis protectebuying a put with a low strike prianselling a call with a higher strike price. This locks in a range of profits anlosses anis a collar. If the strike prices were the same, the hee woulperfect. collar的知识点在讲义什么位置
A portfolio manager wants to hee his bonportfolio against changes in interest rates. He inten to buy a put option with a strike pribelow the portfolio’s current priin orr to proteagainst rising interest rates. He also wants to sell a call option with a strike priabove the portfolio’s current priin orr to rethe cost of buying the put option. Whstrategy is the manager using? BespreStrangle Coll Strale ANSWER: C The manager is long a portfolio, whiis protectebuying a put with a low strike prianselling a call with a higher strike price. This locks in a range of profits anlosses anis a collar. If the strike prices were the same, the hee woulperfect. collar到目前为止，没有在课件中见到，还是我遗漏了？麻烦老师讲解一下collar，我是推了一下其他三个都是错误的，才选出collar的。
Strangle Coll Strale ANSWER: C The manager is long a portfolio, whiis protectebuying a put with a low strike prianselling a call with a higher strike price. This locks in a range of profits anlosses anis a collar. If the strike prices were the same, the hee woulperfect. 课上没学过呀 可以是bull sprea