Hello Lokesh,
There is not an exact cut-off percentage for this, it varies from college to college.
In most colleges, you need to have atleast 50-55% aggregate marks in your class 12 so make sure you have that. Some colleges conduct their entrance exams and on the other hand, some colleges take in students based on merit.
I might be able to help you more if you could specify a college.
Some of the colleges offering B.Sc. Forensic Science are-
Hope this helps.
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