South Sudan officially became an independent sovereign state on July 9, 2011. This followed a successful independence referendum held in January 2011, where the vast majority of the population voted to secede from the Republic of the Sudan. The independence marked the end of a long-standing civil conflict and established the nation as the newest member of the international community at that time.

The capital of Chad is N'Djamena, not Bangui. Bangui is the capital city of the Central African Republic. Therefore, the pairing of Chad and Bangui is factually incorrect, making it the correct choice for this question.

Port of Spain is the capital city of the Republic of Trinidad and Tobago. It serves as the nation's primary administrative, financial, and cultural hub. Despite its name, it is not located in Spain, nor is it a port belonging to the Spanish nation. It is situated on the Gulf of Paria on the northwestern coast of the island of Trinidad.

SUNA stands for the Sudan News Agency. It serves as the official state-run news agency for the Republic of the Sudan, responsible for disseminating national and international news regarding the country's political, social, and economic developments to the public and global media outlets.

BTA, or the Bulgarian Telegraph Agency, is the national news agency of Bulgaria. It was founded in 1898 and serves as the primary source of information for the country's media outlets. It provides comprehensive coverage of political, economic, and social news from within Bulgaria and maintains a network of correspondents to report on international affairs relevant to the Bulgarian public.

The Haitian gourde is the official currency of the Republic of Haiti. The capital and largest city of Haiti is Port-au-Prince. Located on the Gulf of Gonâve, the city serves as the country's primary economic, political, and cultural hub. It is the center of government and the main port for international trade in the nation.

KUNA stands for the Kuwait News Agency. It serves as the official state-run news organization for the nation of Kuwait. Established in 1976, it is responsible for gathering and disseminating news both domestically and internationally, providing official information regarding the government's policies, regional developments, and cultural events within the country.

Port Louis is the capital and largest city of the Republic of Mauritius. It serves as the country's main port, economic center, and administrative hub, located on the northwestern coast of the island in the Indian Ocean.

Pyongyang is the capital and largest city of the Democratic People's Republic of Korea, commonly known as North Korea. It serves as the nation's political, cultural, and economic center, situated on the Taedong River. The city is known for its monumental architecture and its role as the seat of the national government.

Following the collapse of the Soviet Union, Dzhokhar Dudayev declared the independence of the Chechen Republic of Ichkeria in November 1991. This declaration was a pivotal moment in the region's history, leading to significant geopolitical tensions and subsequent conflicts between the Chechen leadership and the Russian Federation as the latter sought to maintain territorial integrity during the post-Soviet transition period.