Concept:The growth of commercial activities in West Africa was largely driven by trade links established with European merchants and colonial powers.
Explanation:Before European arrival, West African trade was mainly local or trans-Saharan.
European contact opened new coastal trade routes.
Europeans set up trading posts along the West African coast.
These posts exchanged goods such as gold, ivory, spices, and later enslaved people for European manufactured products.
This coastal trade greatly expanded commercial activity in the region.
Therefore, the major external contact that boosted West African commerce was with Europeans.
Answer:B. Europeans