Hi Sankvk,
'Review' is a really important part of the GMAT training process, so researching questions that you got wrong on your CATs (and even questions that you got correct, but you're looking to see if there's a faster/easier way) is a smart move. That having been said, those choices are only part of a larger series of Tactics and recommendations that you could use during your studies. Before I can offer you the specific advice that you’re looking for, it would help if you could provide a bit more information on how you've been studying and your goals:
Studies:
1) How long have you studied?
2) What study materials have you used so far?
3) How have you scored on EACH of your CATs (including the Quant and Verbal Scaled Scores for EACH)?
Goals:
4) What is your goal score?
5) When are you planning to take the GMAT?
6) When are you planning to apply to Business School?
7) What Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich