When Light Shines on a Lens Placed on a Flat

Multiple Choice

When light shines on a lens placed on a flat piece of glass,interference occurs which causes circular fringes called Newton's rings.The two beams that are interfering come:

A) from the top and bottom surface of the lens.
B) from the top surface of the lens and the top surface of the piece of glass.
C) from the bottom surface of the lens and the top surface of the piece of glass.
D) from the top and bottom surface of the flat piece of glass.