CTS came for on-campus placement in my college. The aptitude round was easy. Then there was a 1:1 interview with a recruiter. I was asked questions from the basics of my stream. The questions related to computers/programming language were easy. In the HR questions part, all of my responses to "Why do you want to join Cognizant and not any other company?" were negated by the interviewer. Whatever I said, he countered it with an argument. That was the toughest question of my interview.