to the passage below and then answer the question afterwards in the same language as the passage: Passage: Given the many and varied elements and styles of melody "many extant explanations [of melody] confine us to specific stylistic models, and they are too exclusive". Paul Narveson claimed in 1984 that more than three-quarters of melodic topics had not been explored thoroughly. The melodies existing in most European music written before the 20th century, and popular music throughout the 20th century, featured "fixed and easily discernible frequency patterns", recurring "events, often periodic, at all structural levels" and "recurrence of durations and patterns of durations".Melodies in the 20th century utilized "a greater resource of pitch variety than has been the custom in any other historical period of Western music". Bíótilẹjẹ́ pé a ṣì ń lo ìlànà díátónìkì, ó lé ní ìdá mẹ́rin nínú mẹ́ta àwọn kókó orin tí a kò tíì ṣàwárí dáadáa. Àwọn orin tí ó wà nínú ọ̀pọ̀ jùlọ àwọn orin ilẹ
àkókò tó máa fi wà láàyè, bí ohùn rẹ̀ ṣe máa dún tó, bó ṣe máa dún tó, àti bó ṣe máa dún tó