Answer:
Alice qualifies for the opt-in simplified enrollment mechanism.
Step-by-step explanation:
Alice qualifies for the simplified enrollment because the only thing that will change when she retires is that the Spartan Health Plan will not be offered by her employer anymore, but she still will be coverage by the plan.
In the other cases is not a simple enrollment because, in the case of Bob, he has to be enrolled again since he dropped his coverage. In the case of Charlotte, she has coverage from a different company, and it is not planning on retirement, so it will not be a simple enrollment either.