"Whenever real GDP declines, nominal GDP must also decline."
A. Agree. Both real GDP and nominal GDP decline if price falls and output remains constant.
B. Disagree. Real GDP falls if output falls. Nominal GDP can increase if output falls and prices rise.
C. Agree. Both real GDP and nominal GDP decline if output falls and prices remain constant.
D. Disagree. Real GDP falls if output falls. Nominal GDP can increase if output falls and prices fall.
Answer: B. Disagree. Real GDP falls if output falls. Nominal GDP can increase if output falls and prices rise.