hey,

i hope you are good

to calculate best four subject you need to include one language subject (core/elective/functional) , mathematics subject and any two subject from list A ,

you can find list A by clicking on the link mentioned below

https://university.careers360.com/articles/delhi-university-admissions-how-calculate-best-of-four-marks

if you include any other subject other than list A like physical education it will lead a deduction of 2.5 percent in your aggregate

hope this helps!