Final answer:
The Triple Alliance consisted of Germany, Austria-Hungary, and Italy.
Step-by-step explanation:
The nations that formed the Triple Alliance were Germany, Austria-Hungary, and Italy. The Triple Alliance was a military alliance created by German Chancellor Otto von Bismarck in the late 19th century as a way to counterbalance the growing power of Russia and France. Italy initially joined the alliance in 1882, but later abandoned it and joined the Allied Powers in 1915 during World War I.