The correct answer is the following.
A strong question is the kind of question that makes you seriously consider the right answer and options to do something or move on.
The three strong questions that Gary could ask to steer his mind towards new possibilities are: 1.- What do I do to move on with my next relationship, now that I just have learned a couple of things of my last relationship? 2.- What are the problems that affected the relationship that I need to resolve or improve before getting into another relationship? 3.- What were the things that I enjoyed the most in that relationship that I need to maintain in the next one?
The strong question to redirect Gary to new opportunities is, Do I need a new relationship or I can have this intermediate time to consider other priorities such as learning a new language, apply for a summer job, the kind of activities that make me develop new skills and generate professional experience for my future?