What did the policy of unrestricted submarine warfare refer to? ​

According to article 1, why did massachusetts raise their taxes on citizens, and what about the currency of the time made it difficult for citizens to pay these taxes

1. discovered the new world balboa 2. explored the north american southwest hudson 3. his crew was the first to sail around the world vespucci 4. conquered the incas of peru cortes 5. discovered the pacific ocean columbus 6. conquered the aztecs of mexico cabot 7. discovered fishing grounds off newfoundland pizarro 8. looted spanish vessels for england drake 9. claimed the hudson river area for dutch coronado 10. priest who explored the mississippi marquette 11. man for whom the new world is named magellan

Which of the following had the most significant impact in supporting portugal's e fforts to control the indian ocean spice trade