In the ray diagram, a ray refracts at point O. If the line PQ separates two transparent media, which statement BEST describes it?

A) Ray AO is the incident ray, and OB is the normal.
B) Ray OB is the incident ray, and AO is the normal.
C) Ray AO is the incident ray, and OB is the refracted ray.
D) Ray OB is the incident ray, and AO is the refracted ray.