Which event proved that the policy of containment worked?

The collapse of the Soviet Union comes to mind. It was basically strangled to death by containment. Similar to the Anaconda plan used by the North to blockade the south during the American Civil war. You can also argue the fact that most communist states were in the field of containment, with very few or non being outside of it.

If he breaks the law then he had to resign from his post and so he'll lose his/her powers.

It’s a and your welcome