What does the bass clef signify in written music?

The bass clef signifies a specific position for notes on the staff, indicating that the F note is located below middle C on the fourth line of the staff. The bass clef is also known as the F clef because it encircles the fourth line of the staff, which represents the note F. This is particularly important for musicians reading music for lower-pitched instruments or voices, as it helps identify the notes in the bass range.

In contrast, the other options do not accurately describe the function of the bass clef. The first choice refers to a different clef, the treble clef, which indicates that G is placed on the second line. The second option incorrectly describes a measure of musical notes rather than a clef's function. Finally, the fourth choice inaccurately suggests that the clef represents a group of notes, which is not its primary purpose; rather, it establishes a reference for individual notes based on their position on the staff.