How Is Recession Defined by the National Bureau of Economic

How is recession defined by the National Bureau of Economic Research [NBER]?

A) Two consecutive quarters of declining GDP
B) A significant decline in total output, income, employment, and trade for six months to one year
C) A dramatic decline in unemployment for less than six months
D) A sharp increase in money supply and the market rate of interest
E) A significant decline in stock prices over three consecutive quarters of a business year