Which is the definition of a line segment?

Question

a figure formed by two rays that share a common endpoint
the set of all points in a plane that are a given distance away from a given point
a part of a line that has one endpoint and extends indefinitely in one direction
a part of a line that has two endpoints

Answer 1

The definition of a line segment is:

a part of a line that has two endpoints.

This means that a line segment is a finite portion of a line that connects two distinct points.