Question

which figure represents an undefined term?

Explanation:

In geometry, the three undefined terms are point, line, and plane. The first figure represents a ray (a defined term with one - endpoint and extends infinitely in one direction), the second is a line - segment (a defined term with two endpoints), the third is an angle (a defined term formed by two rays with a common endpoint). The fourth figure represents a line which is an undefined term in geometry as it extends infinitely in both directions and has no thickness.

Answer:

The fourth figure (the one with arrows at both ends indicating infinite extension)