Final answer:
Geoffrey Chaucer's best known work is 'The Canterbury Tales', a collection of 24 stories that is a cornerstone of English literature and offers insights into medieval society.
Step-by-step explanation:
Geoffrey Chaucer's best known work is The Canterbury Tales. This landmark literary piece is a collection of 24 stories that run to over 17,000 lines written in Middle English by Chaucer between 1387 and 1400. The Canterbury Tales stands out for its vivid characters, its complex narrative form, and its exploration of a wide range of themes. While both the Book of the Duchess and the Divine Comedy are also notable works, the latter was written by Dante Alighieri, not Chaucer. Therefore, among the options given, The Canterbury Tales is indeed Chaucer's most famous work, being a cornerstone of English literature and offering a window into medieval society through its portrayal of diverse characters from different walks of life sharing stories on a pilgrimage.