1. Name one reason why a predictor variable may be included in a multiple regressionmodel which is used for prediction, even if the variable is not statistically significant.(a) The sample size may be large enough to include the variable, regardless of significance.(b) Inclusion of the variable may be supported by economic theory.(c) Inclusion of the variable may increase R2.(d) The variable may be correlated with other variables in the model.(e) None of the above is such a reason.