Answer:
A.
Step-by-step explanation:
The Punic Wars were a series of war that was fought between the Roman Republic and Phoenician cities in North Africa, in the 3rd and 2nd BC. Carthage, a Phoenician city supported Rome, but when Roman grew in power and army, it rebelled against the Carthage, resulting in Punic Wars.
The Roman Republic was victorious in the Punic Wars, defeating the Carthage, never to rise again. Therefore, the event that led to Roman's expansion is a victory in Punic Wars.
Therefore, option A is the correct answer.