Final answer:
Debussy was influenced by non-Western scales and instruments from the World Exhibition of 1889.
Step-by-step explanation:
Debussy was influenced by the non-Western scales and instruments he encountered at the World Exhibition of 1889. This event showcased music and instruments from various cultures around the world, exposing Debussy to new and unconventional sounds. He incorporated these influences into his own compositions, most notably in his famous piece 'Pagodes' from the suite 'Estampes', where he emulates the sounds of a Javanese gamelan orchestra.