Answer:
D. All of the above.
Step-by-step explanation:
In the Aggregate Expenditure model or approach to GDP, GDP is calculated using the following formula:
GDP = C + I + G + NX (X-M)
Where:
- C = consumption
- I = Investment
- G = Government spending
- NX = Net exports
As can be seen, each of the elements of the equation are necessary to understand (calculate) GDP by the AE approach. Each element is also important to show how macroeconomic equilibrium is reached. Thus, the correct answer is D.