Which of the following is NOT used to describe rhythm?
Beat
Pitch
Tempo
Meter

pitch

Explanation:

Rhythm is, by definition, a strong, regular, repeated pattern of movement or sound. This means that it's a pattern of one thing.

Out of beat, pitch, tempo, and meter, three of them have one thing in common when corresponding to rhythm: monotony. Monotony is the same thing, unchanged in sound and movement.

For example, drawing a straight line continuously.

Beat is a main accent or rhythmic unit in music or poetry.

Pitch is the degree of highness or lowness of a tone.

Tempo is the speed at which a passage of music is or should be played.

Meter is  the rhythm of a piece of poetry, determined by the number and length of feet in a line.

When you listen to music, a rap, or poetry, you can "feel the beat." This means you can pick out the main sound being accentuated, like the "boom-boom-boom" or a clapping track.

Tempo is how fast something goes. A slow song played at a ballet may be different than a rap song, which is fast. Tempo is the speed.

Meter is the rhythm, usually in poetry. It's like a beat and other patterns in the poem.

Pitch is the one that is different. It changes the tone. For example, a high note vs. a low note. That's pitch. When someone swallows helium and talks, their voice is now "high-pitched" because it has a higher-sound tone.

Rhythm does not change—it's a pattern of beats, tempos, and rhythms. Unlike pitch, pitch is musical. Rhythm is not—it's just the pattern.

Pitch is the answer. I hope this helps.