A priority for Justinian I was reconquering lost lands.
Justinian I was the emperor of Byzantine Empire of Rome, from 527 to 565. During his reign, he enacted several reforms which increased accountability and reduced corruption. He was a strong believer in Christianity and so he wrote laws to protect the church.
Justinian I built Hagia Sophia, which became the most important church of the city. He also, reconquered several parts of the empire that were taken by the invaders. He then included those lost lands in his Empire. He also developed Justinian's Law Code, and he created a very strong military force.
It was Justinian's dream to restore the lost glory of the Roman Empire. So for that he sent out his two powerful generals, Belizarius and Narses with an army. Hence, they were successful in regaining much of the lost land.
Hence, option B is correct.
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