The Central Powers included which countries?

Germany, Austria-Hungary, Ottoman Empire and Bulgaria.

Explanation:

The First World War was fought between two influential alliances of nations; the Allied and the Central Powers. Initially, Germany and Austria-Hungary were the member countries of the Central Power but during the course of time, the Ottoman Empire and Bulgaria also joined the Central Powers. The name Central Power was given to this alliance due to the fact that coalition that consisted primarily of "Central" European states.

Some countries are Germany, Austria-Hungary, Ottoman Empire and Bulgaria.