Final answer:
The first Portuguese and Spanish sugar plantations initially relied on knowledge from Muslims and enslaved labor imported from East Africa.
Step-by-step explanation:
The correct answer is 1: East Africa. The first Portuguese and Spanish sugar plantations in the Atlantic islands and Americas relied on knowledge from Muslims and enslaved labor imported from East Africa. African slaves were in high demand for their expertise in growing and processing sugar cane, which had been introduced to Europe by the Arabs during the Middle Ages. This system of plantation agriculture based on sugar production and the use of African slaves became foundation of the Atlantic slave trade.
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