问题如下：
An option portfolio exhibits high unfavorable sensitivity to increases in implied volatility and while experiencing significant daily losses with the passage of time. Which strategy would the trader most likely employ to hedge the portfolio?
选项： Sell short-dated options and buy long-dated
options.
Buy short-dated options and sell long-dated options.
C.Sell short-dated options and sell long-dated options.
D.Buy short-dated options and buy long-dated options.
解释：
ANSWER: A
Such a portfolio is short vega (volatility) and short theta (time). We need to implement a hedge that is delta-neutral and involves buying and selling options with different maturities. Long positions in short-dated options have high negative theta and low positive vega. Hedging can be achieved by selling short-term options and buying long-term options.
老师好，关于Theta,我一共有3个问题：
1、Theta衡量的是随着时间的改变，期权价值的变化，对吗？因此随着时间的流逝，期权的time value下降，所以期权的价值下降，所以Theta小于0；
2、越临近到期日，ATM的Theta的绝对值增加，ITM和OTM的Theta的绝对值减小；
3、这道题的experiencing significant daily losses with the passage of time这句话，代表的意思就是当前这个组合的Theta小于0吗？要对冲这个风险，就要使Theta大于0，因此要short 一个期限短的(ATM)的option.
