The Bureau of Economic Analysis of the U

The Bureau of Economic Analysis of the U.S.Government releases advance estimates of quarterly GDP in the first month following quarter end.In the second month,it provides a preliminary estimate.In the third,it provides a "final" estimate (though even this estimate is subject to annual revisions) .Over the past 30 years,the average revision of GDP growth rate from advance to final has been approximately what fraction of a percentage point?

A) 1/4.
B) 1/3.
C) 1/2.
D) 2/3.