I chose B as computer generated. The one I liked best was A.
Band-in-a-Box has a “generate melody” function that is described in this video:
It also has a solo track band in its Mixer. Typically, to an existing tune or one you’ve entered and have displayed as a lead sheet with chords and melody you can have BIAB generate either a midi or “Real” solo track. There are piano tracks, for example, with Kenny Barron playing solo piano. If you have a tune set up to to accompany your melodica playing with bass, rhythm piano, and drums, the melody will be played by a midi instrument, and you can select a Real Track instrument to play a Kenny Barron solo. This will be Kenny’s actual playing, his actual piano sound and improvisation. I don’t understand the details, but the solo track is a composite of improvisational segments for common chord progressions that Kenny laid down for BIAB during countless hours in the studio. However much of that he did, I guess the engineers did the rest, and you can have it in any key you want. You can also switch from seeing the melody in the lead sheet window to seeing the scoring for Kenny’s solo. Midi solos can also be generated.
Lots of composers use BIAB, and I’m sure there’s a whole lot more to it than what I understand. But satisfying use of it requires getting a version with all the Real Tracks and Styles, which costs about $500 — a terrific bargain, however. And it requires an incredible investment of time and energy.