单选题
Buy land, advised Mark Twain; they're not making it any more. In fact, land is not really scarce: the entire population of America could fit into Texas with more than an acre for each household to enjoy. What drives prices upward is a 24 between rude demand and limited supply in the great metropolises (大城市) like London, Mumbai and New York. In the past ten years 25 property in Mayfair, in central London, can go for as much as £55,000 ($82,000) per square meter. A square mile of Manhattan residential property costs $16.5 billion. Even in these great cities the scarcity is 26 . Regulatory limits on the height and density of buildings 27 supply and blow up prices. A recent analysis by academics at the London School of Economics 28 that land-use regulations in the West End of London blow up the price office space by about 800%; in Milan and Paris the rules push up prices by around 300%. Most of the enormous value captured by 29 exists because it is well-nigh impossible to build new offices to compete those 30 away. The costs of this misfiring (哑火的) 31 market are huge, mainly because of their effects on individuals. High housing prices force workers towards cheaper but less productive places. According to one study, 32 in the Bay Area around San Francisco would be about five times larger than it is but for fight limits on 33 . Add up these costs in lost earnings and unrealised human potential, and the figures become dizzying. A. artificial B. collision C. constrain D. construction E. contain F. credits G. description H. employment I. estimates J. govern K. inevitable L. landowners M. profits N. property O. residential