All of the Following Considerations Are Important in Explaining the Observed

All of the following considerations are important in explaining the observed interference patterns produced by light reflection from a thin film except

A) the superposition of incident light with reflected light.
B) the superposition of reflections coming from separate points on the reflecting surface.
C) the time average of the intensity of the light at places that are not nodes.
D) the relative magnitudes of the E-fields contributing to the resultant nodal points.