Huygens' Theory for the Construction of Wavefronts States That

Multiple Choice

Huygens' theory for the construction of wavefronts states that

A) the angle of incidence is always less than the angle of refraction.
B) the time required for light to travel from one point to another is either a maximum or minimum.
C) only parallel light produces interference and diffraction.
D) each point on a wavefront is itself the source of a secondary spherical wave.
E) all wavefronts are spherical.