Choice "C" is correct. If there is an increase in the resources available in an economy, the economy will be capable of producing more goods and services. This increase is really an increase in the long-run aggregate supply (potential GDP). On the aggregate supply and demand chart, the long-run aggregate supply line (LRAS) is the vertical line that represents the potential or equilibrium level of output. If that line shifts to the right, then the economy is capable of expanding, but it will not automatically expand just because the line shifts to the right.
Choice "a" is incorrect. Just because there is an increase in the resources available in an economy, it does not mean that more goods and services will automatically be produced. There would have to be increased demand (a shift upward in the aggregate demand line) for more goods and services to actually be produced by suppliers.Choice "d" is incorrect. If there is an increase in the resources available in an economy, the standard of living in the economy will not necessarily rise. It could rise, but it will not necessarily do that.
Choice "b" is incorrect. If there is an increase in the resources available in an economy, the technological efficiency of the economy will not automatically improve. This statement is backwards. An increase in technological efficiency of an economy will normally increase the resources available in the economy and potentially result in increased productivity.