Which best describes a walking bass line? a) melodic line played on bass guitar b) melodic line played on an upright bass guitar c) short repeated sequence of notes which can become a theme of a piece d) repeated harmonic line in the bass with notes from a set chord progression i know for sure it is not a. i do, however, think it's d., but i'm not positive. i also hope it was appropriate to put this question under 'arts'.