Suppose the Official Rate of Unemployment Reported by Statistics Canada

Suppose the official rate of unemployment reported by Statistics Canada is 7.2%.One reason this is likely to be an understatement of the amount of "true" unemployment is that

A) the official rate is a measure of gross flows into and out of unemployment rather than net flows.
B) discouraged workers who have given up searching for a job,but would take one if offered,are not included.
C) the official rate is a measure of net flows into and out of unemployment rather than gross flows.
D) Statistics Canada does not have a good measure of the numbers of people entering the labour force,so the denominator in the measured ratio is smaller than in reality.
E) seasonal workers are not included at all in the official data.