Which motion is the best out of the following for vocal music

Conjunct motion
Disjunct motion
Vertical motion
Horizontal motion

The best motion for vocal music would generally depend on the specific context and style of the piece. However, conjunct motion is often considered preferable for vocal music.

Conjunct motion refers to melodic motion that moves stepwise or in small intervals, where notes are close to each other in pitch. This type of motion is typically easier for singers to navigate and provides a smoother and more legato (connected) melodic line. It allows for a more seamless and natural flow of the voice, making it easier for singers to produce a cohesive and pleasing sound.

Disjunct motion, on the other hand, involves larger melodic leaps or jumps between pitches. While disjunct motion can add drama, excitement, or expressive qualities to a piece, it can be more challenging for singers to execute accurately and may interrupt the overall fluidity and ease in which the vocal line is performed.

Vertical motion and horizontal motion are not terms commonly used to describe melodic motion in vocal music. Vertical motion is more related to chord progressions and harmonic movement, while horizontal motion might refer to the direction of voices within a musical texture. These terms do not specifically address the melodic quality of a vocal line.

Again, it is important to consider the specific musical context and style when determining which type of motion is best for a given piece of vocal music.