Who required music to be standardized ?

In music, a standard is a musical composition of established popularity, considered part of the "standard repertoire" of one or several genres.[1][2] Even though the standard repertoire of a given genre consists of a dynamic and partly subjective set of songs, these can be identified by having been performed or recorded by a variety of musical acts, often with different arrangements. In addition, standards are extensively quoted by other works and commonly serve as the basis for musical improvisation.[3] Standards may "cross over" from one genre's repertoire to another's; for example, many jazz standards have entered the pop repertoire, and many blues standards have entered the rock repertoire.

Standards exist in the classical, popular and folk music traditions of all cultures. In the context of Western classical music, the standard repertoire constitutes most of what is considered the "teaching canon", i.e. the compositions that students learn in their academic training.[4] The standard repertoire varies according to the different eras, movements and scenes within a genre, meaning that the extent to which a given composition is considered a standard or "repertoire piece" may vary greatly.[5] However, some repertoires (e.g. concert piano) have become particularly static, giving rise to a divide between "standard-repertoire performers" and contemporary music advocates.[6]

Explanation:

10 songs

explanation:

i gave you 10 songs yay!

i believe the answer is: a.  abstract forms were often used to represent human figures.

representing human figures in abstract forms is often used in the geometric period, not hellenistic  period.   during the hellenistic  period,   aesthetic value derived from creating arts which mimic the actual shape of a certain object or individuals.

hope this ! < 3