Final answer:
Magellan was convinced to trust Balboa's instinct to sail west to reach Asia in 1519 because of the discovery of the South Sea or what we now call the Pacific Ocean
Step-by-step explanation:
Magellan was convinced to trust Balboa's instinct to sail west to reach Asia in 1519 because of the discovery of the South Sea or what we now call the Pacific Ocean. Balboa had already explored and reached the eastern shore of the South Sea, proving to Magellan that a westward route to Asia was possible. This discovery gave Magellan the confidence to embark on his own expedition, which ultimately led to the first circumnavigation of the globe.
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