Final Answer:
Octavian's naval forces defeated those of Antony and Cleopatra at the Battle of Actium in 31 BCE, marking a crucial event that led to the end of the Roman Republic and the rise of the Roman Empire. So, the correct answer is a) Actium.
Step-by-step explanation:
Historical Context: The Battle of Actium, fought in 31 BCE, was a decisive naval conflict between the forces of Octavian (later known as Augustus) and the combined forces of Mark Antony and Cleopatra.
Key Participants: Octavian, the adopted heir of Julius Caesar, faced off against Mark Antony, a prominent Roman general, and Cleopatra, the Queen of Egypt. The battle unfolded in the Ionian Sea off the western coast of Greece.
Outcome and Implications: Octavian's naval forces emerged victorious, leading to the defeat of Antony and Cleopatra. This victory marked a turning point in Roman history, resulting in Octavian's rise to power, the end of the Roman Republic, and the establishment of the Roman Empire.
Therefore, the correct answer is a) Actium.