Which Was a Triumph of Quantum Electrodynamics (QED)

Multiple Choice

Which was a triumph of quantum electrodynamics (QED) ?

A) QED predicted the existence of three carrier particles before they were discovered in laboratory experiments.
B) QED unites the strong and weak nuclear forces.
C) QED is an example of a theory of everything.
D) QED successfully explains the origin of quantum mechanical fluctuations in the CBR.