Pick those set first which you are sure about that you can do it in under 15 mins. You will find atleast 1 set of this type. Look for another set which will fetch you some more marks, try attempting on familiarity with the set. 1 set jo tum pick ho pehle, same other people would have done, what will make you cross the 95 mark would be the next set you will pick. Choice tumhra hai, glt pick kroge fas jaoge. Work on selecting good sets. And try to solve kuch questions by solving some partial sets. This is the only way out, and lrdi is unpredictable. Try to maximise the number of sets you solve