Today I have tried to restrict a user group to post in a specific category. The idea was that I was going to create a page where a specific category post needs to show. Then I created a loop for a specific category to show in that page. But the problem was that users have different option for category. That means they can select any category that they want and if the post it to other category except that intended category by me then that will not show up in my page. So I had to force them to select a specific category. Then I found the following plugin that does it for me. Really nice one.