Ask Anything
This is usually the last part of an interview and possibly the shortest, however, it is as important as the other sections, this is the opportunity for you to show some interest in working for the company, so doing some research about the project you were assigned to or any other detail about the company will definitely come in handy.
caution
NOT demonstrating interest might become a reason to not select you, even if you did well in all the other parts of the interview