Honesty might be the best policy, but that doesn't stop jobseekers from stretching the truth. According to Ron Friedman, an award-winning social psychologist and author of "The Best Place to Work, a whopping 81 percent of people lie during interviews.

That's likely why SpaceX and Tesla CEO Elon Musk asks one simple interview question to catch a candidate's bluff: What were the most difficult problems you faced and how did you solve them?