Respuesta :
Answer:
D. They are quadrilaterals that have opposite sides equal in length.
Step-by-step explanation:
Rectangles and parallelograms both have 2 sets of parallel sides. The parallel sides are of equal length.
Rectangles are special parallelograms that have 2 sets of corners that have 90 degree angles
Squares are special rectangles that have all 4 sides of equal lengths.