Big cities today are confronted with very serious problems. Transport is a【1】difficulty: s

ome planners believe in【2】transport system; others believe in making it possible for citizens to move 【3】in private cars. There are several ways of 【4】a public transport system. Sometimes it is built under the ground; sometimes it is on the【5】 , and sometimes it is even above ground level,【6】in parts of New York and Tokyo for example. In most cases, of course, it is a【7】of some or all of these elements.

The【8】of the city centers has also been a problem in the last 30 years. The hearts of many cities have become poorer and poorer,【9】more and more crime and violence,【10】the people who can afford to have moved out to the【11】. This is the opposite of the situation 100 years ago,【12】wealthy people lived in the center, and the poor lived 【13】the outskirts of the city.

Ecological problems also【14】 , as factories and cars pollute the air, trees are cut down to make【15】for urban clearways, and crowded conditions cause garbage to【16】in the streets.

In order to solve these problems, some planners believe we should limit the size of our cities, perhaps by restricting population, or perhaps by offering【17】jobs in the provinces. Others believe that cities cannot be limited in size and that the problems must be solved in a【18】of ways—by creating green areas, building【19】houses for everybody, stopping factory pollution,【20】motor transport, and so on.

(1)

A．minor

B．major

C．little

D．small