Dear GMAT experts,
............................
Thank you in advance for your answer!

ipavlovic,

Do you mean this question is verbatim from a real GMAT administration? If so, GMAC prohibits display or discussion of these questions outside of the test center. In the last year, websites have been shut down and scores have been canceled as the result of "live" questions getting out into the wild.

If you can find a similar question in legally available test prep materials, I'd be happy to walk you through it!

Some friend of mine passed it to me to as challenge question from the "real" GMAT. I don't know is it true or not, but I removed it from message board to avoid any trouble. This question might be from some other prep sources, but anyhow I apologize because I didn't know that is possible to post only questions related to the Veritas Prep course.