Hello Aspirant ,
If you fail in three subjects in class 12 you will have to repeat the class 12 again, and you will be able to attempt the exam next year only , so i woulg suggest you to prepare well next year , attempt all the previous year questions you can , make your own notes and study daily .
You are only allowed to give re examination if you fail in only one subject since you failed in 3 subjects you can not give re examination .
Hope this helps.
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