Question

A ______ is a line segment whose ends lie on a circle's circumference. A. Chord B. Secant C. Radius D. Tangent

Answer 1

 A radius is a line segment with one endpoint at the center of the circle and the other endpoint on the circle.

A chord is a segment that also has endpoints on the circle, but the line does not need to cross through the center.

 A secant is a line that intersects with a circle at 2 different points

A tangent is a line that intersects with the circle at one point

Answer 2

A chord.
This is because a chord is a line segment that is within the circle
A secant goes continuously (not a line segment) but is similar to a chord
Radius is the length from the middle of a circle to the perimeter. 1 end is in the center one is on the circumference ( question says "ends" as in both ends)
Tangent is a line outside of the circle that is perpendicular to a line inna circle