Final answer:
The Central Powers in World War I included Germany, the Austrian Empire, the Ottoman Empire, and later Bulgaria. Italy initially allied with Germany and Austria-Hungary but switched sides to join the Allied Powers in 1915.
Step-by-step explanation:
The countries that comprised the Central Powers during World War I were Germany, the Austrian Empire, the Ottoman Empire (Turkey), and later Bulgaria. Initially, Italy was part of the Triple Alliance with Germany and Austria-Hungary, but it did not join the Central Powers once the war broke out. Instead, Italy switched sides in 1915 to join the Triple Entente, which included Great Britain, France, and Russia. The Triple Entente, later known as the Allied Powers, expanded to include other nations such as Japan, Belgium, and the United States, among others. Hence, the correct answer to the question 'Which countries comprised the Central Powers?' is 'b) Germany' considering the list provided in the question.