(2 point) User can choose one major, a gender and a sort -type, then click "Filter" button, reload the list of students to show only students of the selected major, selected gender by the order of selected sort-type.
(1 point) After reloading the student list according to the data filtering request, the selected major,gender and sort-type must be set to two DropDownList and Ratio Button Group as the Figure 2 below.
