20) Which of the following is not true?
A) When a series has the same average growth rate from period to period, then it can be approximated by including trend in a regression.
B) Dummy variables can be used to address the problem of seasonality in regression models.
C) Yt = β0 + β1St + β1St-1 + β2St-2 + β3St-3 + Ut, it is possible to estimate the long-run effect of a change in St on Yt.
D) Serial correlation of the error term in time series regression invalidates the estimates and t-values of the estimates.
E) Including a time trend in a time series regression is equivalent to detrending the dependent variable but not the independent variables.