State of Eligibility means the state from which you have passed 12th examination. State is mentioned in 12th marksheet. Also you can use aadhar or voter card or any government ID card as your state code of eligibility proof.

But make sure the state mentioned in your government ID card matches with the state mentioned in your 12th marksheet.

So you can use 12th marksheet or government ID card as state code of eligibility proof.

All the best.