All of these explain a change in long-run aggregate supply except: increases in business taxes. increases in productivity. changes in government spending. changes in resource prices.

Long-term aggregate supply (LAS) gives the representation of the potential output and  the relationship between the price level and output in the long-run.  The input prices are not constant. The changes in aggregate demand only cause a temporary change in an economy's total output, so the long-run aggregate supply curve is perfectly vertical.  In the long-run, there is exactly one quantity that will be supplied. The changes in resource prices is not LAS, but short-term aggregate supply, because depends on the price of the input. 

Ithink the answer is true.