GMAT Critical Reasoning (CR) | for decades, countries have measured wheat field productivity using th

for decades, countries have measured wheat field productivity using the Wheat Field Productivity Index (WFPI), which is equal to the average number of pounds of grain harvested per acre of wheat. In 2005, Mlatnia's WFPI was 60 pound per acre more than Italy's WFPI. In 2006, Maltania's WFPI was 75 pound per acre more than Italy's. Therefore, Malania's wheat field productivity must have increased during that period.

Which of the following, IF TRUE, provides strongest support for the conclusion above?

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