Final Answer:
The shape described is a square. The square, being a specific case of a rectangle with additional conditions of congruent sides and right angles at all corners, meets all the criteria outlined in the given description.
Step-by-step explanation:
The characteristics mentioned—two pairs of parallel sides, all four sides congruent, diagonals bisecting each other, and right angles at all four vertices—are defining properties of a square. A square is a special type of rectangle where all sides are equal in length, all angles are right angles (90 degrees), and opposite sides are parallel. Additionally, its diagonals bisect each other at right angles, creating congruent pairs of triangles. These properties collectively confirm that the given shape must be a square. Its symmetry and equal sides fulfill the criteria outlined for a square, making it the only quadrilateral that fits all the specified conditions.
The presence of parallel sides and congruent diagonals suggests symmetry and balance within the shape. Moreover, the right angles at the vertices ensure the square's uniformity, showcasing identical measures for all angles. The square, being a specific case of a rectangle with additional conditions of congruent sides and right angles at all corners, meets all the criteria outlined in the given description.