Private telecommunications firms invest heavily in upgrading a nation's high-speed fiber-optic broadband infrastructure. All other things being equal, the result of this investment for that country's economy would be
a movement along both its aggregate demand curve and long-run aggregate supply curve.
a shift in its aggregate demand curve and a movement along its long-run aggregate supply curve.
a movement along its aggregate demand curve and a shift in its long-run aggregate supply curve.
a shift in both its aggregate demand curve and long-run aggregate supply curve.