Bulgaria is a country located in southeastern Europe on the Balkan Peninsula. What is the capital city of Bulgaria?

Introduction / Context:
This question deals with European geography and asks you to identify the capital city of Bulgaria. Bulgaria is a southeastern European nation with a long history and diverse cultural heritage. Its capital city, Sofia, is a major political and economic center in the Balkans. Remembering that Sofia is the capital of Bulgaria is essential for general knowledge exams that cover European countries and their capitals.

Given Data / Assumptions:

The country mentioned in the question is Bulgaria.
You must choose its capital city from the options given.
The options include Yaounde, Sofia, Moroni, and None of these.
Each named city, except Sofia, is the capital of a different country outside Europe.

Concept / Approach:
The underlying concept is that Sofia is the capital of Bulgaria. Sofia lies in western Bulgaria near the Vitosha mountain and serves as the center of government, culture, and transport for the country. Yaounde is the capital of Cameroon in Central Africa, and Moroni is the capital of the Comoros, an island nation in the Indian Ocean. None of these is a distractor option that should not be selected once you recognize Sofia as the correct match for Bulgaria.

Step-by-Step Solution:
Step 1: Focus on the country name, Bulgaria, located in southeastern Europe.Step 2: Recall that Sofia is the capital and largest city of Bulgaria.Step 3: Review the options and identify Yaounde as belonging to Cameroon and Moroni as belonging to the Comoros.Step 4: Since Sofia uniquely pairs with Bulgaria, eliminate the other cities as incorrect.Step 5: Because the correct capital appears in the list, do not choose None of these; select Sofia as the answer.

Verification / Alternative check:
Maps of Europe show Bulgaria with Sofia as its capital, often highlighted with a distinctive symbol. Encyclopedias, travel guides, and official Bulgarian government sources all state that Sofia is the seat of national institutions and the largest city in the country. Yaounde and Moroni are mentioned only in the context of their own nations and regions, never as capitals in southeastern Europe. This consistent pattern across references confirms that Sofia is the correct answer.

Why Other Options Are Wrong:
Yaounde is the capital of Cameroon, a country in Central Africa. Moroni is the capital of the Comoros, an island state off the coast of East Africa. Neither of these cities is located in Bulgaria or Europe. None of these is incorrect because the correct capital, Sofia, is explicitly given in the options. Thus, Yaounde, Moroni, and None of these must all be rejected for this question.

Common Pitfalls:
Students sometimes confuse lesser known capitals from Africa and Europe, especially when studying many countries at once. Another source of error is choosing None of these too quickly without verifying all available options. To avoid such mistakes, it helps to group countries by continent and memorize associated capital cities, reinforcing them with mental images or brief stories. Associating Bulgaria with Sofia and the Balkan region makes it easier to recall the correct answer under exam pressure.

Final Answer:
The capital city of Bulgaria is Sofia.