SAT Inferences Question

In 1990, oil prices rose 90% between August and October, creating what economists term an oil shock. Although oil shocks have occurred multiple times since 1945, a broadly applicable description of how oil shocks affect economies at the national level has proved elusive, a problem typically attributed to the fact that oil shocks' effects are substantially conditioned on country-specific characteristics (oil import-export ratios, most importantly). Recently, however, Gbadebo Oladosu et al. showed that economists' estimates of national economies' responsiveness to oil shocks are highly heterogeneous even within a given country and time frame—ranging by more than a factor of five in the case of Australia during a recent oil shock, for instance—suggesting that Which choice most logically completes the text?