Light Travels from Inside a Building to Outside Through a Pane

Multiple Choice

Light travels from inside a building to outside through a pane of glass.Which of the following is true regarding the phase change upon reflection in the case?

A) A 180^o phase change occurs at the inside surface but not at the outside surface.
B) A 180^o phase change occurs at the outside surface but not at the inside surface.
C) A 180^o phase change occurs at both the inside surface and the outside surface.
D) No phase change occurs at either the inside surface or the outside surface of the glass.