Which of the following ideas were spread as a side effect to the African gold-salt trade? A
printing press
B
iron-working
С
Islam
D
Hinduism

C

Explanation: While the motivations of early conversions remain unclear, it is apparent that the early presence of Islam in West Africa was linked to trade and commerce with North Africa. Trade between West Africa and the Mediterranean predated Islam, however, North African Muslims intensified the Trans-Saharan trade.

the fact that could also be added to column b is that during world war ii, specifically between the years 1941 and 1945, japan expanded its territory towards the indonesian territory in what was known later as part of the "pacific war". in that time, japan could conquer the philipines, singapore,   borneo, central java, malang, cebu, sumatra and various other islands of the area, therefore expanding its territory for a brief period of time.

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explanation: