GMAT Critical Reasoning (CR) | Despite a steady stream of pessimistic forecasts, our economy continue

Despite a steady stream of pessimistic forecasts, our economy continues to grow and prosper. Over the last 15 years the service sector of our economy has greatly expanded. Last year alone, 500,000 Americans found employment in the service sector. In the face of evidence such as this, one cannot argue that our economy is wilting.

Which of the following, if true, would most seriously undermine the conclusion drawn above?

(A) Many Americans who took jobs in the service sector last year were also