Which of the following biconditional is equivalent to the definition:
"An endpoint is a point at the end of a segment or at the start of a ray."
None of the other answers are correct
OA point is an endpoint if and only if it lies on a segment or a ray.
OA point is an endpoint if and only if it is a point.
OA point is an endpoint if and only if it is at the end of a segment or the start of a ray.
OA point is an endpoint if and only if it is the start of a ray.