I had given mhtcet exam . I had filled non maharastra cat.in app. form of mhtcet and now in CAP round can I change my category to type C

Since you have filled the form with some details then those details are usually considered until your verification is done but as far as changing a category or caste or any other details regarding admissions are concerned you can't change it from open option to an reserved option like for example if you are an open candidate and you filled obc by mistake then it will be considered but the vice versa won't be considered. So I expect that you won't be able to change that.