The interviewer wants to hear that you feel accomplished through teamwork. Talk about a time when you felt fulfilled through a team setting or project collaboration.
An example may be a time when you worked on a team project in University, a recent work collaboration, or possibly an extracurricular experience such as coaching a little league team.
Discuss the positive results of the teamwork and how you attained a positive outcome as a group.
"The most rewarding team work experience that I have had was in my last year of university. We were assigned a project in teams of 4 which accounted for quite a large part of our grade. I believe everyone pulled more than their own weight because so much was at stake. Team work is very rewarding when everyone has sometime to win, or lose."
"One of my most rewarding team work experiences was while I was attending University. I learned so much by working with my classmates. I gained new problem solving skills and learned a lot from their research preferences."