Is there any difference in the level of difficulty among the different sets of CBSE class 12?

CBSE QUESTION SETS are designed keeping in mind the level of difficulty that should be appropriately distributed among students from every section like average, below average and brilliant students. So in every set out of the three sets, there is one or two brainstorming and twisted questions for the genius lads and lasses. These twisted questions are all that they play with in different sets. Different sorts of questions from this section are fired at the students. That’s how different sets get their tag of difficulty. Most of the questions are same with some numerical values changed at times, mostly they don’t even do that. So more or less the sets are same.