Which power-couple unified spain and completed the reconquista

Ferdinand and Isabella were the biggest power couple of there time

They are remembered for sponsoring Christopher Columbus' voyage across the Atlantic in 1492

the world may never know

no options provided, here,but the answer to this question is often: a historian cites a japanese newspaper article published a year after the end of world war ii in order to draw conclusions about the effect of the war on the japanese economy.

clearly from the answer, the historian alludes to historical sources,and records to aid in analyzing and drawing conclusion on the effect of the war on the economy of japan.