Early Roman society was divided up into two major classes - plebeians and patricians. 

Patricians were the 'noblemen' or aristocrats of Ancient Roman society. They held most of the positions in Roman assemblies, were the only group allowed to be part of the priesthood, and generally held far more power than most others. One could only become a patrician through birthright.

The plebeians included everyone else, excluding slaves. They comprised the lower and working class folk. Compared to the patricians, they held very little power in the early Roman empire, and had to work much harder to attain wealth and social status.

Livy, also known as Titus Livius, lived in Rome in the first century BCE. He is one of the most famous Roman historians and is most notable for comprehensive history he wrote on the development of the Roman Republic.

The Aeneid is an epic poem written by the Roman author, Virgil, around 20 BCE. In The Aeneid, Virgil tells the story of the foundation of Rome by refugees fleeing the Trojan War.

Claudius Ptolemy lived in Alexandria, in Roman Egypt, in the second century CE. The key to understanding this question is to know that the last name Ptolemy was a name associated with Hellenistic or Roman rule in Egypt.

The Latin phrase Mare Nostrum translates as “Our Sea.” It was the Roman name for the Mediterranean, and reflects their hegemonic desires. We might compare the Roman belief in their ownership of the Mediterranean with the American concept of Manifest Destiny.

Emperor Tiberius, the second Emperor of the Roman Empire, is partially remembered for his gloomy disposition and the lack of enthusiasm he felt for ruling. Tiberius’ reputation as a melancholic individual probably stems from the writings of Pliny the Elder. Pliny’s writings provide a great deal of the primary history of this time period.

The first Roman pantheon was constructed on the orders of Marcus Agrippa. Agrippa was a military commander, architect, public works manager, and close friend to the first Roman Emperor, Augustus Caesar. The pantheon was a monumental temple to the Roman Gods. It would later become a Catholic church.

Marcus Agrippa was a close friend of Octavian (later Augustus Caesar). Agrippa contributed to Octavian’s rise to power by leading part of his navy at the Battle of Actium. After Augustus Caesar became Emperor in 27 BCE, Marcus Agrippa was charged with leading the renovation of Rome. He led the construction of the Pantheon, as well as aqueducts, temples, and numerous public baths and houses.

The correct answer is pietas (duty, loyalty). This refers to the great sense of loyalty the Roman citizens felt towards their country. While dignitas (dignity), gravitas (seriousness), comitas (humor), and firmitas (tenacity) were all considered important traits of a Roman citizen, pietas is the only option that refers to the duty a citizen had to serve the Republic.

Julius Caesar, while an important figure, was not known for his philosophical contributions, so he would not be the best choice. Nero was known for corruption and self-interest rather than intellectual pursuits, so he too would not be a good choice. Constantine the Great was a religious man and crafted the Edict of Milan, but he was not a Stoic, so he would not be a good answer. Lucius Verus was the co-emperor of Marcus Aurelius but he was not a Stoic, so he would not be the best choice. Finally, Marcus Aurelius was the author of Meditations and a renowned Stoic, so he would be the best choice.