(c) South Sudan
The correct answer is (a) Cameroon.
The Congo Basin is a sedimentary basin of the Congo River. It is located in Central Africa, in a region known as west equatorial Africa. The Congo Basin region is sometimes known simply as the Congo. It contains some of the largest tropical rainforests in the world and is an important source of water used in agriculture and energy generation.
The Congo Basin spans across six countries—Cameroon, Central African Republic, Democratic Republic of the Congo, Republic of the Congo, Equatorial Guinea and Gabon.
Nigeria, South Sudan, and Uganda are not part of the Congo Basin.
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