What does a slur indicate in musical notation?

A slur in musical notation indicates that the notes under the slur should be played smoothly and connected. This means that the musician should not articulate each note separately with a distinct attack but rather allow the sound to flow from one note to the next in a legato manner. The absence of breaks or pauses between the notes creates a seamless effect that is essential for conveying the lyrical quality of the music.

In contrast, other options don't accurately describe the function of a slur. For instance, the idea of separating the notes distinctly would pertain to articulations like staccato, while repeating the melody aligns more closely with the concept of a repeat sign or similar markings. Lastly, indicating a slight pause relates to the concept of a fermata or breath marks, which are not reflected in the slur notation. Thus, the primary purpose of slurs is to facilitate smooth transitions between the indicated notes, defining the flow of the musical passage.