The Wave-Particle Duality Theory Is the First Adequate Explanation of Which

Multiple Choice

The wave-particle duality theory is the first adequate explanation of which one of the following observations about the hydrogen atom?

A) More than one possible orbit exists for the electron.
B) An infinite number of possible orbits exist for the electron.
C) Only certain energies are possible for the orbiting electron.
D) More than one momentum is possible for the orbiting electron.
E) None of these is correct.