Suga or J-Hope from BTS

In three to five sentences, list and briefly explain the three elements of music

Most of the written music that has been preserved from the middle ages is a. sacred. b. for flute and guitar. c. polyphonic. d. dance music.

Need some ! asap i need to figure out 3 major changes in bridges over time and why these changes to adapt to both improvements in technology and changing social links would also alot.