(a) Cameroon 

(b) Nigeria 

(c) South Sudan 

(d) Uganda 

Ans: a

Explanation:

The Congo Basin is Known as the “lungs of Africa”, it is the largest carbon sink in the world, absorbing more carbon than the Amazon. The Congo Basin spans across six countries—Cameroon, Central African Republic, Democratic Republic of the Congo, Republic of the Congo, Equatorial Guinea and Gabon.

Hence, option a is correct.

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