Which is the definition of a ray?

Question

a part of a line that has one endpoint and extends indefinitely in one direction
the set of all points in a plane that are a given distance away from a given point
lines that lie in the same plane and do not intersect
a part of a line that has two endpoints

Answer 1

The correct definition of a ray is:

a part of a line that has one endpoint and extends indefinitely in one direction.