Which of the following allowed for widespread exploration starting in the 1400s?

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Widespread exploration was made possible in the 1400s by the growth in wealth in Europe as well as new technological developments in ship building that made traveling far distances more attainable. The political regimes of Europe became more centralized at this time and were able to raise more funds to help support the acquisition of new trade routes and territories around the globe. New ships were built and developed at this time that also allowed for further international travel. 
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