Final answer:
The Renaissance era in music was characterized by a shift from monophonic music to an emphasis on polyphony and harmony, leading to more complex and richly textured compositions.
Step-by-step explanation:
The change that shaped the music of the Renaissance was b) Emphasis on polyphony and harmony. During the Renaissance era, there was a shift from monophonic music, which has a single melodic line, to polyphonic music, characterized by multiple, independent melody lines. Composers of the time began to create more complex and harmonious pieces that often included four or more parts, leading to richer textures in music. The invention of the Gutenberg press played a significant role in spreading music and musical theories far and wide, contributing to this transformation. This period also saw an increase in the use of the interval of the third, which had previously been considered a dissonance during the Middle Ages.
Secular music gained wider distribution, reflecting the rise of humanistic thought and the burgeoning bourgeois class. Furthermore, the modal characteristics of the music began to evolve towards the end of the Renaissance, hinting at the advent of tonal music. The influence of the Franco-Flemish school contributed to the development of a common musical language that was polyphonic in nature, reaching a peak with composers like Palestrina and William Byrd.