In the churches of Luther and Calvin, the musical emphasis was on: a. a return to Gregorian chant. b. spectacular polyphonic works. c. congregational singing. d. the inclusion of instruments in the service.

C. Congregational singing

Explanation: Congregational singing is the practice of the congregation joining in the music of a church, either in the form of hymns or in the form of the office of the liturgy. Several reasons why congregational singing is so important in the life of a church are:

1. It unifies the congregation

2. It is a great way to praise the lord

3. It is a wonderful way to pray together.

4. It solidifies and teaches spiritual truth.

5. It can aid in revival

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