Hello Nilesh,
Yes the OBC category student will get seat on the basis of its rank in OBC. But sometimes it happens you get a seat in general category as well if your rank is quite good.
See for the same seat and if yiu belong to OBC category and still the seat of general category hasn't filled up yet you'll get seat in general category but you have to submit the documents of OBC category in this way the person who has a lower rank and belongs to OBC category gets a chance as you have already got admission in general category.
Hope this will help you to clear your confusion still if you have doubt feel free to reach out.
All the best!
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