When We Say That an Electromagnetic Field Is "Quantized," We

Multiple Choice

When we say that an electromagnetic field is "quantized," we mean that

A) whenever it interacts with atoms, it must deposit an entire "quantum" of energy at each interaction.
B) its energy is "digitized" to have either 0, 1, 2, 3, etc. units of a basic energy increment.
C) it impacts a viewing screen as tiny bundles of radiation.
D) All of the above.
E) None of the above.