This nation's province of Haut-Katanga is surrounded on three sides by the nation of Zambia, and this nation has a small coastline along the Atlantic between Angola and its exclave of Cabinda. This nation's capital was once known as Leopoldville, and that same capital is now the largest French speaking city in the world. That capital lies across the country's namesake river from a similarly named country's capital of Brazzaville. For 10 points, name this Central African country with its capital at Kinshasa, formerly known as Zaire.
a) Congo
b) Democratic Republic of the Congo
c) Republic of the Congo
d) Gabon