不能理解为啥会有adverse selection risk

问题如下：

An insurance company offers a policy that pays out if a worker becomes unemployed. Which of the following risks are applicable?

选项：

Moral hazard, but not adverse selection

Adverse selection, but not moral hazard

Moral hazard and adverse selection

Neither moral hazard nor adverse selection

解释：

C. There is both moral hazard and adverse selection. The behavior of a policyholder with a job might change (he or she will not be as concerned about being fired as he or she would be if there were no policy) and an employee without a job will not look as hard to find one. This is moral hazard. Also, the policy is likely to attract people with less secure jobs. This is adverse selection.