Option A) Point and line Option
B) Plane and line Option
C) Point and ray Option
D) Ray and line
Answer: The correct pair of undefined terms used to define the term “parallel lines” is Option B) Plane and line.
Parallel lines are defined as lines that lie in the same plane and do not intersect. A plane is a flat surface that extends infinitely in all directions. A line is a straight path that extends infinitely in both directions. Therefore, to define parallel lines, we need both the concept of a plane and a line.
Two lines are said to be parallel if they lie in the same plane and do not intersect, and this definition requires both the concepts of a plane and a line.