Final answer:
The naval battle where Marcus Vipsanius Agrippa and Octavian defeated Mark Antony in 31 BCE was the Battle of Actium.
Step-by-step explanation:
The naval battle in which Marcus Vipsanius Agrippa commanded the forces of Octavian and defeated Mark Antony in 31 BCE was the Battle of Actium.
At the Battle of Actium, Octavian's naval forces clashed with the combined forces of Mark Antony and Cleopatra. Octavian emerged victorious, leading to the downfall of Antony and Cleopatra and the establishment of Octavian as the sole ruler of Rome.
The Battle of Actium was a significant event in Roman history, marking the end of the Roman Republic and the beginning of the Roman Empire under Octavian, who later took the name Augustus.
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