What characteristic is shared by church music of the Middle Ages and the Renaissance?

The characteristic shared by church music of the Middle Ages and the Renaissance is the use of a cappella performance practices. During both periods, vocal music was primarily performed without instrumental accompaniment, particularly in sacred contexts. This practice allowed the focus to remain on the text and the clarity of vocal lines, which were often designed to convey religious messages. In the Middle Ages, Gregorian chant exemplified this tradition, emphasizing monophonic, unaccompanied vocal music. As music evolved into the Renaissance, while polyphony and other vocal textures emerged, the a cappella style continued to be prevalent in church music, promoting the purity of vocal sound and the importance of the human voice in worship.

In contrast, the other characteristics mentioned in the options are not as representative of both periods. The use of instruments became more common in later Renaissance music but was less characteristic of the earlier Middle Ages, where instruments were often avoided in church settings. The emphasis on harmony developed significantly throughout the Renaissance, while earlier Medieval music was mostly scalar and less focused on harmony in the way we understand it now. Complex polyphony, while notable in Renaissance music, was not a feature of much of the earlier medieval repertoire, which largely relied on simpler, monophonic textures.