Trade among west African countries is less developed mainly because

A.

they were ruled by different colonial powers which created a barrier to communication

B.

the products of one country are basically similar to those of the others

C.

there are no international railway lines to transport the bulky items of trade across the borders

D.

of ethnic sentiments of people in one country against the other

E.

no west African country has surpluses of commodities to export to the other countries

Correct answer is A

No explanation has been provided for this answer.