I would classify as follows -

Class A: Operating angle = 360 degrees.
Class AB: Operating angle = 180-200 degrees.
Class B: Operating angle = 180 degrees.
Class C: Operating angle = less than 180 degrees but usually between
150 and 110 degrees.

I don't know about the others but they are probably not defined by
operating angles.
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Reg, G4FGQ.