Which technique involves broken chords played by the left hand while the right hand plays the melody?

The technique that involves broken chords played by the left hand while the right hand plays the melody is known as Alberti Bass. This technique alternates between the lowest and highest notes of a triad or broken chord, creating a harmonic foundation that supports the melody played in the right hand.

In Alberti Bass, the left hand typically plays a repeating pattern, which can provide a rhythmic and harmonic backdrop while allowing the right hand to focus on the melodic line. It is a common stylistic feature found in piano music from the Classical era and is named after the composer Domenico Alberti.

Arpeggio refers to the notes of a chord being played in succession rather than simultaneously. Stride involves a left-hand technique where the player alternates between bass notes and chords, often spanning a greater distance across the keyboard, and is commonly used in jazz. Counterpoint, on the other hand, is a compositional technique that involves the relationship between two or more independent melodies, rather than the specific right-hand melody and left-hand accompaniment idea presented in the question.