阅读理解
In recent weeks media outlets in the U.S. have been fretting over what would ordinarily be considered good news—the roaring American economy, which has brought low unemployment and, in some places, a labour shortage. Owners and managers have complained about their problems in finding people to fill low-wage positions. "Nobody wants to do manual labour any more," as one trade association grandee told The Baltimore Sun, and so the manual labour simply goes undone. Company bosses talk about the things they have done to fix the situation: the ads they've published; the guest-worker visas for which they've applied; how they are going into schools to encourage kids to learn construction skills or to drive trucks. But nothing seems to work. Blame for the labour shortage is sprayed all over the US map: opioids are said to be the problem. And welfare, and inadequate parking spaces, and a falling birthrate, and mass incarceration, and—above all—the Trump administration's immigration policies. But no one really knows for sure. The textbook solution to the labour shortage problem—paying workers more—rarely merits more than a line or two, if it's mentioned at all. So unwilling are business leaders to talk about or consider this obvious answer that Neel Kashkari, the president of the Minneapolis Federal Reserve Bank, scolded them last year: "If you're not raising wages, then it just sounds like whining." If you study the Bureau of Labor Statistics' numbers on wages for nonsupervisory workers over the past few decades, you will notice that wage growth has been strangely slow to pick up. Hot economies usually drive wages up pretty promptly; this recovery has been running since 2009 and it has barely moved the needle. How could such a thing happen in this modem and enlightened age? Well, for starters, think of all that whining we're hearing from the US's management, who will apparently blame anyone and do anything to avoid paying workers more. Every labour-management innovation seems to have been designed with this amazing goal in mind. Every great bipartisan political initiative, from free trade to welfare reform, points the same way.
单选题36.The labour shortage is mainly concentrated in___