Final answer:
The end of the Ottoman Empire was spurred by European military superiority, territorial overextension, internal decline, and the effects of World War I culminating in the signing of the Armistice of Mudros and the loss of territories.
Step-by-step explanation:
The factor that led to the end of the Ottoman Empire at the conclusion of World War I can be attributed to a combination of internal issues and decisive defeats during the war. European military might and Ottoman territorial overextension were significant historical factors in the decline of the empire. This decline started after the Battle of Lepanto and was further exacerbated by losses to the Austrians and the rise of nationalism within its territories, leading to the independence of Greece, Serbia, Romania, and Bulgaria.
The Ottoman Empire's status as 'the sick man of Europe' was evident through governmental corruption, lack of technological advancement, and weak leadership. The signing of the Armistice of Mudros in 1918 marked the Ottoman Empire's exit from World War I, and subsequent territorial partitions by the Allied forces greatly reduced the empire's influence, preceding its disintegration and the establishment of the Republic of Turkey.