What was guido d'arezzo's contribution to musical notation? a. hexachords b. staff lines c. rhythm d. articulation marks e. neumes

The answer is : staff lines. He devised an arrangement of lines and spaces that developed into the musical staff. Two of Guido D'Arezzo's primary contributions to music history : 1. developed a 4-line staff circa. 1025 2. wrote a text on music ca. 1026 called "Micrologus"

staff lines

Explanation:

its the answer for apex

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