Hello!
For the best of 4 calculation of 12th board percentage, here's an article that can help you out based on the course you want:
https://university.careers360.com/articles/delhi-university-admissions-how-calculate-best-of-four-marks
The four subjects to be considered each have to follow these guidelines, please check if Physical Ed. follows it in your case.
Good luck!
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile