When you check the options women institute you will only get options of the colleges that are only for women but along with that if you check more categories will be filtered.
For eg: If a person checks women's institutes along with colleges in Delhi. A filtered college list will be shown in which only women colleges from Delhi will be shown. Hence, these filters are for your convenience.
Note: If you don't check the women institute filter it will be easier to mark the choices. That is you will get both co-ed and women institutes to choose from in choice filling portal.