Final answer:
The true statement among the options provided is that the Romans' first code of law was established around 450 B.C.E., which refers to the Twelve Tables.
Step-by-step explanation:
The answer that is a true statement regarding Roman society and law is: The Romans' first code of law was established around 450 B.C.E. This refers to the Twelve Tables, a set of laws that became the foundation of Roman law. The statement about the plebeians being wealthy and influential does not hold true as plebeians were the common citizens of Rome, and they initially could not hold public office or marry patricians, though they gained more rights over time, eventually being able to become consuls and pass laws. A patrician was not a soldier who was a former enslaved person but rather a member of the aristocratic elite who had ancient roots in the city and were initially the only ones allowed to hold public office. Lastly, the Roman Republic did not last over 1,000 years; it lasted for about five centuries before transitioning to the Roman Empire.