The correct answer is D. All of the above.
An econometric model is a mathematical representation of an economic system or process. It is used to study the relationships between economic variables and to make predictions about future economic activity.
To build an econometric model, you need to have a computer with large auxiliary storage capacity to store the data and the model, a data base of economic data to use as input for the model, and a model base of quantitative analysis programs to use to estimate the model parameters.
Option A is correct because a computer with large auxiliary storage capacity is needed to store the data and the model. The data can be very large, and the model can also be large, so it is important to have a computer with enough storage space to store both.
Option B is correct because a data base of economic data is needed to use as input for the model. The model needs data on economic variables such as GDP, inflation, and unemployment to estimate the model parameters.
Option C is correct because a model base of quantitative analysis programs is needed to use to estimate the model parameters. The model parameters are estimated using statistical methods, and these methods require quantitative analysis programs.
Option E is incorrect because all of the above are needed to build an econometric model.