(John of the clue crew reporting)  Because the geometric shape here has all right angles, it's called a rectangle; when they're not right angles, it becomes this type of quadrilateral
[DOC] [TLE] 1,014 Practice Questions for the New GRE, 2nd Edition | Aayush ... [PAR] That is what this book and Cracking the New GRE, 2012 Edition are all about.