Question

which is a property of an angle? has two sides that each extend forever in both directions has two endpoints has two center points has two rays that share a common endpoint

Explanation:

An angle is formed by two rays that share a common endpoint called the vertex. The sides of an angle are rays, not lines (which extend forever in both directions), and it has one vertex (not two endpoints or two center - points).

Answer:

has two rays that share a common endpoint