Although fluctuations in unemployment are a phenomenon in constant evolution, the natural rate of unemployment varies considerably lower than the actual unemployment rate. In fact, factors that may not be natural rate of actual unemployment.
  Which of the following would be the natural rate of unemployment?
I. Young people can enter the labor market at an earlier age.
II The economy is in expansion over the last ten years.
III. The government raises the minimum wage for manual workers.
IV The unions have become more demanding in terms of negotiations for higher wages.
  A. II only
  B. All these
  C. I, III and IV only
  D. II, III and IV only
  E. III and IV