Yet there are also many ways our social statistics underestimate the degree of labor-market-related hardship. The unemployment counts exclude millions of fully employed workers whose wages arc so low that their families remain in poverty. Low wages and repeated or prolonged unemployment frequently internet to undermine the capacity for self-support. Since the number experiencing joblessness at some time during the year is several times the number unemployed in any month, those who suffer as a result of forced idleness can equal or exceed average annual unemployment, even though only a minority of the jobless in any month really suffers. For every person counted in the monthly unemployment tallies, there is another part-time working because of the inability Io find fulltime work, or else outside the labor force but wanting a job. Finally, income transfers in our country have always focused on the elderly, disabled, and dependent, neglecting the needs of the working poor, so that the dramatic expansion of cash and in kind transfers does not necessarily mean that those failings in the labor market are adequately protected.
As a result of such contradictory evidence, it is uncertain whether those suffering seriously as a result of labor market problems number in the hundreds of thousands or the tens of millions, and, hence, whether high levels of joblessness can be tolerated or must be countered by job creation and economic stimulus. There is only one area of agreement in this debate----that the existing poverty, employment, and earnings statistics are inadequate for one of their primary applications, measuring the consequences of labor market problems.
Which of the following docs "labor market problems" (Line 1, Para. 1) refer to？

A. Shortage of jobs providing adequate income.
B. Deficiencies in the training of the work force.
C. Trade relationships among producers of goods.
D. The overall causes of poverty.