Hello
I can't tell you about other state boards. But yes about CBSE, in it there's a provision of Improvement exam for those who have passed in whole but want to improve their marks in one or more papers. And after the exam you will be given a Seperate marksheet with your improved marks ONLY. You will have to show both of your marksheets at the time of your admission. And in DU you will not face any obstruction in getting admission in your dream college.
Hey
No Chinmayrepeating Class 12 does not affect you admission in Delhi University. As per the University of Delhi, applicants must have completed their class 12 examination from the CBSE or any other recognized state board. There is no minimum age bar mentioned for applicants.
Please note: Delhi University Admission 2019 for the UG Programmes conducted through both merit and entrance will begin with the release of the online application form. In the application form candidates need to enter the marks secured by them in the best four subjects.
From May 15, 2019 Online registration for UG Programs (Merit and Entrance Based) will commence.
for more details: https://university.careers360.com/articles/du-admission
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