The correct option is D Square
Let's analyze the clues:
1. The figure is a quadrilateral.
So, the figure is definitely not a triangle.
2. It has all sides equal.
A rectangle has only opposite sides equal.
So, the shape is not a rectangle.
3. It has all the interior angles equal.
Between square and rhombus, a square has all the interior angles equal to 90°.
Hence, the correct figure is a square.