There are other areas of the application that it asks about clubs and teams. Answer the one above truthfully, it is straight forward. Student council or student senate are the members from each high school class that works with the faculty on projects that benefit the student body. Some schools have class president for each grade and other schools only have student body officers, meaning all 4 classes these officers (president, vp, sec & treasurer) are usually held by the seniors. All the other members of the student senate/council are referred to as delegates or members.
As I stated above there are other places in the application for team info. Varsity, JV, captain or co captain. And also for clubs such as club officer etc. even for those clubs outside of school such as 4-H.