Indicate, in response to the description provided, which element of the circle is:
$$C$$: segment that connects any two points on the circumference.
$$r$$: segment that connects the center with any point of the circumference.
$$o$$: point in the plane which is at the same distance from all points of the circumference.
$$D$$: the largest string that exists in a circumference.
$$S$$: line that cuts any two points of the circumference.
Development:
The elements of the figure are the following ones:
$$C$$ is a string, an element that connects any two points on the circumference.
$$r$$ is the radius of the circle.
$$O$$ is the center of the circle.
$$D$$ is the diameter of the circle, the longest chord.
$$S$$ is a secant line to the circumference.
Solution:
$$C$$: string, $$r$$: radius, $$O$$: center, $$D$$: diameter, $$S$$: secant line.