How Do We Account for the Two Hypotheses of Vesicular

How do we account for the two hypotheses of vesicular fusion and retrieval?

A) There is more experimental support for the classical pathway of neurotransmitter release.
B) There was very little support for the classical pathway of neurotransmitter release, therefore the kiss-and-run pathway is currently the favored pathway.
C) Both pathways are portions of a larger pathway and therefore there should be one hypothesis.
D) The kiss-and-run pathway is likely used at lower rates of neurotransmitter release while the classical pathway predominates at higher rates of neurotransmitter release.