To construct a chronological timeline of significant events that led up to the formation of the Roman Empire, the correct order would be:
- Gracchi brothers’ assassinations (133–121 BCE)
- Sulla’s march on Rome (88 BCE)
- First Triumvirate (60 BCE)
- March across the Rubicon (49 BCE)
- Ides of March (44 BCE)
- Second Triumvirate (43 BCE)
- Battle of Actium (31 BCE)
Thus, the correct response from the options provided is:
Gracchi brothers’ assassinations, Sulla’s march on Rome, First Triumvirate, march across the Rubicon, Ides of March, Second Triumvirate, Battle of Actium.