The pattern A B A C A D A outlines which form?

This was one of the stipulations for the artistic contest that Brunelleschi and Ghiberti competed in: a. A quatrefoil frame

b. A classical order. c. A classical bust. d. A pentagon frame.

All musical cultures, Western and non-Western, make use the octave. Do they all use it in the same manner or are

there differences? Explain.

What will be an ideal response?