Which term indicates a slow tempo?

The term that indicates a slow tempo is "Adagio." In musical terminology, tempo markings help convey the speed at which a piece of music should be played. Adagio specifically denotes a slow, leisurely pace, often suggesting a relaxed or dignified character in the music.

The other terms represent faster tempos: Vivace indicates a lively and fast pace; Presto refers to an extremely fast tempo; and Allegro suggests a cheerful and brisk tempo. Each of these terms conveys a sense of energy and movement that contrasts with the slower, more measured feel of Adagio, making it the appropriate choice for indicating a slow tempo.