Final answer:
Montresor tells the story to the audience in 'The Cask of Amontillado' to recount his plan for revenge and seek validation for his actions.
Step-by-step explanation:
In 'The Cask of Amontillado,' Montresor tells the story to the audience because he wants to recount his plan for revenge and how he successfully executed it. By sharing the story, Montresor is able to relive the satisfaction he felt in carrying out his revenge on Fortunato. Additionally, Montresor may also seek validation and acknowledgment from the audience for his cunning and deceitful actions.