In New Orleans, Moon Walk—— a pathway along a stretch of the Mississippi--now provides the

public access that had previously been denied. It's a charming place, where one night recently a band played on the walk as tourists and residents of the adjacent Vieux Carre (the Old Quarter or French Quarter) strolled past. A few feet west, the paddlewheeler Natchez sounded its whistle, signaling its imminent departure.

Now the city plans to extend public access to the area adjoining Moon Walk in an ambitious design that will, the city hopes, be a part of its development for the next world's fair. This more ambitious concept for the waterfront will be likely to stir considerable debate as competing projects vie (竞争) for the opportunities for profit. The development will therefore require substantial participation, cooperation and scrutiny (详细审查) by citizens to make sure that while private profitability is maintained, the public's needs are satisfied, too.

The joint efforts of environmentalists, business-people, civic leaders and politicians have transformed abandoned, derelict (废弃的) port landscapes in cities throughout America into exciting commercial and recreational centers. Examples are the Cannery in San Francisco, the Riverfront Walk in San Antonio, Faneuil Hall Market in Boston and Harborplace in Baltimore.

It's easy to understand why the port areas were neglected. While many cities were growing up along rivers, lakes and natural harbors, depending on water-borne commerce, waterfronts thrived. After World War Ⅱ, however, technological changes in transportation— improved planes and airports, the interstate highway system, larger tracks for freight trains and containerized shipping--rendered many old port facilities obsolete. Waterfront areas became peripheral (外围的) to the life of the city. Piers were abandoned, and the waterfronts lay idle in many older cities, paralleling the more general urban decay.

With the 1970's came a period of reflection on this condition and a resurgence (苏醒) of urban pride. urban renewal stopped being a license for large-scale demolition (破坏); politicians and planners took a hard. look at their available resources and began to experiment with new development techniques. Waterfronts became one focus of the large urban revitalization effort.

The primary purpose of this passage is to describe ______.

A．business expansion of urban areas

B．Moon Walk in New Orleans

C．the causes of urban decay

D．the renewal of waterfront areas