Final answer:
The gods allowed the twin serpents to devour Laocoön and his sons as a punishment for his warning to the Trojans about the wooden horse left by the Greeks. This is depicted in the Hellenistic sculpture group of Laocoön and His Sons.
Step-by-step explanation:
The Vergilian commentator Servius offers the reason that the gods allowed the twin serpents to devour Laocoön and his sons as a punishment sent by Athena or Poseidon, depending on the version of the story. This punishment was a result of Laocoön's warning to the Trojans about the Greeks' wooden horse, which upset the gods.
The sculpture group of Laocoön and His Sons, created in the early first century CE, depicts this scene from Virgil's epic, The Aeneid, and showcases the drama, tension, and pathos characteristic of the Hellenistic style.