Database design of a settings system : Guys can you please help me with my database design I'm trying to do a mini system which includes a Category, and under that category has many subcategory, and under that subcategory has many topics, and under that topics has many questions. So I'm going to put Add buttons for four of them Category>SubCategory>SubCategoryTopic>Question 

all of them have to be dynamic obviously but I was planning to display it as a dropdown then I thought that it wouldn't look friendly when there are many topics stored. but yeah I was wondering if you guys could help me with my database design

