The vast geographical feature which forms a border between nigeria, chad, cameroon and niger, is a__

The Answer is Lake.
This Vast geographical feature is also called "Chad Lake". There is a vast area which forms a border between Nigeria, chad, Cameroon and Niger is a lake.
Chad is an Area with four bioclimatic zones and in the world it is one of the 48 land-locked countries. The second largest lake in the west Africa is Lake Chad.

which question?

explanation:

which question r u talking about?

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