Concept:The Nigerian colonial economy depended on cash-crop agriculture for export revenue.
Explanation:During the colonial period, Nigeria's major exports were agricultural products.
Cocoa, palm produce, and groundnut were the leading cash crops.
These three commodities accounted for about 70% of total export earnings.
Palm produce and cocoa came mainly from the southern regions, while groundnut was produced in the north.
Crude oil became important only later, and garri is not an export crop.
Answer:C. cocoa, palm produce and groundnut