求解释。。。。。

问题如下：

A straddle is created by a long position in call option at $2 and a long position in put option at $4, with the same strike price of $20 and same expiration date. At expiration the stock price is $25, then the profit or loss of this strategy is:

选项：

A.

a loss of $1.

B.

A gain of $1

C.

A gain of $4.

D.

A loss of $4.

解释：

A is correct.

考点： straddle

解析：

Profit = max(0,S – X) – c + max(0,X –S)– p = max(0, 25 – 20) – 2 + max(0, 20 – 25)– 4= -1.

Therefore, this strategy will have a loss of $1.