The correct answer and explanation is:
The correct answer is (E) All of the above.
The development of musical notation in Western music was not the result of a single cause but rather a confluence of interconnected needs that emerged during the Middle Ages, primarily within the Catholic Church.
A major driving force was the desire for liturgical uniformity. Leaders, most notably the Emperor Charlemagne around the 9th century, sought to standardize religious practices, including the music used in Mass, across the vast Holy Roman Empire. Oral tradition was unreliable, leading to many regional variations of the same Gregorian chants. A written system was essential to disseminate a single, authorized version of the chant repertory, fulfilling the goal described in option (D).
This vast repertory of chants was also growing in complexity. As music evolved from simple unison melodies to early forms of polyphony where multiple vocal lines were sung simultaneously, remembering the intricate parts purely by ear became exceedingly difficult and impractical. Notation became a necessary tool to accurately preserve and perform these more complicated works, which supports the reason given in option (B).
From a practical standpoint, the process of teaching this music was incredibly inefficient. Monasteries were centers of learning, and training new monks and choirboys to memorize hundreds of chants could take as long as a decade. Innovators like Guido of Arezzo in the 11th century explicitly developed tools, such as the musical staff and clefs, to solve this problem. His goal was to create a system where a singer could learn a new piece independently, drastically reducing training time. This directly addresses option (A).
While the modern concept of composer credit was not a primary motivator, the act of writing music down did begin the long process of attributing works to individuals, supporting option (C) as a consequence and emerging factor. Therefore, all these reasons contributed to the invention of musical notation.
