Final answer:
The offering of sacrifices was not part of the imperial ritual in Justinian's church of Hagia Sophia, with the emphasis instead on ceremonies in line with Christian practices. The correct option is c.
Step-by-step explanation:
The element that was not a part of the imperial ritual in Justinian's church of Hagia Sophia was c. the offering of sacrifices. In the Christian faith, particularly during the reign of Emperor Justinian, the practice of animal sacrifice was disapproved. The ceremonial aspects that were included involved the emperor's ceremonial entry, the lighting of candles, and the chanting of hymns during religious services.
Imperial rituals in the Hagia Sophia focused on celebrating the Divine Liturgy, with emphasis on Christian rites and the emperor's role within the context of the church. This reflected the Christian rejection of pagan customs, such as animal sacrifices, and the celebration of the Eucharist during religious ceremonies. Hence, c is the correct option.