Which of the following is a chord?
A chord is a line which touches the circle at two distinct points on its circumference.
A segment is an area cut by a chord in a circle and hence cannot be a chord.
An arc is a part of the circumference and hence cannot be a chord.
The radius is not a chord as it does not touch the circle at two points on its circumference.
The diameter is a chord since it touches the circle at two points on its circumference.