Final answer:
The strategy of leapfrogging, or island hopping, involved selectively controlling islands to cut off Japan's supply lines.
Step-by-step explanation:
The strategy of leapfrogging, also known as island hopping, called for d) selectively controlling islands to cut off Japan's supply lines. This strategy was used by the Allied forces, led by General Douglas MacArthur, during World War II in the Pacific theater. The goal was to capture strategically important islands that could be used as bases for further attacks, while bypassing heavily defended or less significant islands. By seizing islands and cutting off Japanese supply lines, the Allies were able to advance towards Japan without engaging in direct assaults on heavily fortified positions.