It is given that the quadrilateral has four congruent sides and four right angles .
Because of four right angles, it can be a square or a rectangle . And is is given that the sides are congruent.
Congruent sides means equal sides. And in the quadrilateral, all four sides are equal. So it cant be a rectangle.
THerefore the only possibility is of a square. And hence the correct answer is a square .
