Hello there!
When registering for a State Counselling, you are supposed to give your high school information. This information is required to check whether you have scored according to the qualifying marks or not, which in turn confirms your eligibility. You are only allowed to give your marks in numbers and no alphabets are needed to be entered in that space. So, the answer for your query is - no, you should not redux C before HSC number in Tamil Nadu MBBS counselling registration.
For more information on expected colleges you can get on the basis of your NEET score, use this college predictor tool.
https://medicine.careers360.com/neet-college-predictor?icn=QnA&ici=qna_answer
I hope this answer resolves your query.
Good Luck!
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