NO.PZ2020021205000013
问题如下：
What is the sign of the delta of a long position in (a) a call option and (b) a put option?
选项：
解释：
The delta of a long position in a call option is positive.
The delta of a long position in a put option is negative.
call option不论 long position或short positon，delta call 都是positive吧？
put option 不论long position或short positon，delta put 都是 negtive吧？
谢谢老师。
