The major purpose of Spanish and Portuguese voyages of exploration were establishing sea routes to the Indies to make profits from trade (C). The seafaring exploration led to the discovery by Europeans of the Americas which was not the initial purpose of the voyages.
I believe C is the answer.
The purpose of Spanish and Portuguese voyages of exploration was primarily to establish sea routes to the Indies to profit from trade, as indicated by option C. This was driven by the desire for direct access to Asian spices and other valuable goods after the Ottoman Empire monopolized traditional trade routes. The explorations ultimately led to significant discoveries and the establishment of empires in the New World.
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