Which option best describes the standard Alberti bass pattern?

• A. A melodic figure in the right hand
• B. A rapid scale run in the left hand
• C. A chordal, block-chord accompaniment
• D. A left-hand pattern of broken chords in the order low-high-middle-high

Answer: (D)

The pattern is a left-hand accompaniment where each chord is broken into four notes in the order lowest pitch, highest pitch, middle pitch, highest pitch, repeated as the harmony continues. In practice, you play the lowest note of the triad, then the highest, then the middle, then the highest again, cycling this pattern for each chord. This creates a steady, arpeggiated foundation that supports the right-hand melody without crowding it. For example, in C major the triad C–E–G would be played as C–G–E–G repeatedly. It’s named for its association with Classical-era keyboard music and composers like Alberti.

The other descriptions don’t fit: a melodic figure in the right hand describes a melody, not the left-hand accompaniment; a rapid scale run in the left hand is a scalar passage, not a broken-chord pattern; and a block-chord accompaniment uses simultaneous chords rather than a broken, arpeggiated sequence.