These are all pleasing to look at with smooth bokeh. I like C the most for the focus right where my eye would go, the front of the centre ring. The slightly wider DoF shows off most of the flower detail. D would be my 2nd pick for the same focus point with more OOF. A,B the focus is further back. It starts where the flower is cut in half. E,F are a nice rendering with a bit of a pale, flat look. Reduced color? contrast? You are testing us with more than just the look of the lens.