Which shape is a four-sided polygon with all angles and sides equal?

• A. Rectangle
• B. Trapezoid
• C. Kite
• D. Square

Answer: (D)

A square is a four-sided figure where every side is the same length and every interior angle is the same (each angle is 90 degrees). That combination—all sides equal and all angles equal—matches the description exactly. A rectangle shares all right angles, but its sides aren’t all the same length, so it doesn’t fit. A trapezoid has only one pair of parallel sides and typically unequal sides, so it also doesn’t fit. A kite has two pairs of equal adjacent sides, but not all four sides or all four angles are equal, so it doesn’t fit either.