A parallelogram with four right angles is called?

A parallelogram with four right angles is specifically defined as a rectangle. By definition, a parallelogram is a four-sided figure (quadrilateral) where opposite sides are parallel, and if all angles measure 90 degrees, the shape conforms to the properties of a rectangle.

While a square also has four right angles, it is a special case of a rectangle where all sides are of equal length. A rhombus can have equal sides but does not necessarily have right angles. A trapezoid, on the other hand, has only one pair of parallel sides and does not meet the criteria of a parallelogram.

Thus, identifying a parallelogram with four right angles as a rectangle is accurate, as it encompasses the defined properties of both figures.