SAT Central Ideas and Details Question

Mauricio Drelichman and Hans-Joachim Voth's research into the debt defaults of Philip II (who ruled an empire including Spain and much of Belgium from 1556 to 1598) relates to other work on European early modern state finance, including Hoffman and Norberg's research on the relationship between state finance and political development. But Drelichman and Voth's unique contribution to the field is their reconstruction of the earliest extant set of annual fiscal records for any sovereign state, demonstrating in turn that Philip's defaults were caused by short-term cash shortages, not long-term unsustainable debts. Which choice best states the main idea of the text?