Explanations:Understanding the properties of geometric shapes is fundamental in geometry. Shapes can be broadly categorized into two main types: polygons and non-polygons. Polygons are closed shapes with straight sides and corners, while non-polygons include shapes like circles and ovals, which are smooth and continuous without any sides or corners.
A circle is defined as a set of points in a plane that are all at the same distance from a central point. This distance is known as the radius. The circle is perfectly symmetrical and has no sides or corners. It is a fundamental shape in geometry and is used in various mathematical and real-world applications.
An oval, on the other hand, is a shape that resembles a circle but is elongated. It is also a smooth, continuous curve without any sides or corners. Ovals are often used in design and architecture due to their aesthetically pleasing and fluid appearance.
When considering the properties of shapes, it is important to distinguish between those that have sides and corners (polygons) and those that do not (non-polygons). Triangles, squares, and other polygons are defined by their sides and corners, whereas circles and ovals are defined by their smooth, continuous curves.
In the context of the question, the correct answer is "Circle /oval" because these shapes are the only ones among the given options that do not have any sides or corners. Triangles and squares, being polygons, have sides and corners, and thus do not fit the description provided in the question.