which figure represents an undefined term?

which figure represents an undefined term?
Answer
Brief Explanations:
In geometry, the three undefined terms are point, line, and plane. The first option represents a ray (a part - of a line with one endpoint and extends infinitely in one direction), the second is a line - segment (a part of a line with two endpoints), the third is an angle (formed by two rays with a common endpoint), and the fourth represents a line which is an undefined term. A line extends infinitely in both directions.
Answer:
The fourth figure (the one with a line extending infinitely in both directions with points X and Y on it)