Question

which is defined using the undefined terms point and line?
angle
circle
parallel lines
ray

Explanation:

• An angle is defined using two rays (which are defined using points and lines) sharing a common endpoint (a point).
• A circle is defined using a set of points equidistant from a center point, but the key undefined terms here for the question's context (point and line) - a circle's definition is more about the set of points at a distance (uses the concept of distance which is a derived measure, not directly just point and line in the simple combination as needed here).
• Parallel lines are defined as two lines in a plane that do not intersect. While it uses the term line, it doesn't directly combine point and line in its basic definition in the same fundamental way as a ray.
• A ray is defined as a part of a line that starts at a point (endpoint) and extends infinitely in one direction. So it directly uses the undefined terms point and line.

Answer:

ray