Final answer:
c. The priests were not invisible most of the time behind a screen.
Step-by-step explanation:
The correct answer is C) The priests were invisible most of the time behind a screen.
In the imperial ritual of Justinian's church of Hagia Sophia, the congregation filled the space under the domes and sang hymns. The emperor and patriarch met under the dome at key points in the liturgy. However, the priests were not invisible most of the time behind a screen. They were actively involved in the rituals and visible to the congregation.