Final answer:
The Sarcophagus with reclining couple
Step-by-step explanation:
The work of art that illustrates how Romanized the Etruscans had become by the first century BCE is the Sarcophagus with reclining couple.
The sarcophagus shows the influence of Roman culture on the Etruscans, with the individuals depicted in a Roman style and attire. This reflects the assimilation and adoption of Roman customs and artistic styles by the Etruscans during this period.
Learn more about Roman influence on Etruscans