Answer:
Technically, this figure is all of them, but more specifically, a square
Explanation:
Definitions:
Rectangle: Quadrilateral that is equiangular
Rhombus: Quadrilateral that is equilateral
Square: An equiangular, equilateral quadrilateral
Counting the sides of all sides show us that this quadrilateral is equilateral, and knowing that all x = ₙ and y = ₙ are perpendicular shows us that this quadrilateral is equiangular.
So, this figure is all of those shapes, most specifically a square.