角度：在下拉列表中重置ng-switch

This seems like such a mundane task, but i can't seem to reset the dropdowns to the original state. I'm using ng-switch for each value from the dropdown. I have researched this and I can't seem to find any documentation pertaining to my problem. There are similar questions that have been answered, and I have looked at the angularAPI, but none seem to fix my problem.This seems like such a mundane task, but i can'