补全短文
because whatever to in A. 【T13】______it results in a declining market for manufactured goods B. which is stable or 【T14】______decline C. 【T15】______the consequences may be D. that official attitudes 【T16】______population growth vary from country to country One of the difficulties in carrying out a worldwide birth control program lies in the fact 【T17】______ depending on the level of industrial development and the availability of food and raw materials. In a developing country where a vastly expanded population is pressing hard upon the limits of food, space and natural resources, it will be the first concern of government to place a limit on the birthrate, 【T18】______. In a highly industrialized society the problem may be more complex. A decreasing birthrate may lead to unemployment【T19】______. When the pressure of population on housing declines, prices also decline and the building industry is weakened. Faced with considerations such as these, the government of a developed country may well prefer to see a slowly increasing population, rather than one 【T20】______.