Traffic statistics paint a gloomy picture. To help solve their traffic woes, some rapidly growing U.S. cities have simply built more roads. But traffic experts say building more roads is a quick-fix solution that will not alleviate the traffic problem in the long run. Soaring land costs, increasing concern over social and environmental disruptions caused by road-building, and the likelihood that more roads can only lead to more cars and traffic are powerful factors bearing down on a 1950s-style construction program.

　　The goal of smart-highway technology is to make traffic systems work at optimum efficiency by treating the road and the vehicles traveling on them as an integral transportation system. Proponents of the advanced technology say electronic detection systems, closed-circuit television, radio communication, ramp metering, variable message signing, and other smart-highway technology can now be used at a reasonable cost to improve communication between drivers and the people who monitor traffic.

　　Pathfinder, a Santa Monica, California-based smart-highway project in which a 14-mile stretch of the Santa Monica Freeway, making up what is called a “smart corridor”, is being instrumented with buried loops in the pavement. Closed-circuit television cameras survey the flow of traffic, while communication linked to property equipped automobiles advise motorists of the least congested routes or detours.

　　Not all traffic experts, however, look to smart-highway technology as the ultimate solution to traffic gridlock. Some say the high-tech approach is limited and can only offer temporary solutions to a serious problem.

　　“Electronics on the highway addresses just one aspect of the problem: how to regulate traffic more efficiently,” explains Michael Renner, senior researcher at the world-watch Institute. “It doesn’t deal with the central problem of too many cars for roads that can’t be built fast enough. It sends people the wrong message”. They start thinking “Yes, there used to be a traffic congestion problem, but that’s been solved now because we have advanced high-tech system in place.” Larson agrees and adds, “Smart highway is just one of the tools that we use to deal with our traffic problems. It’s not the solution itself, just pan of the package. There are different strategies.”

　　Other traffic problem-solving options being studied and experimented with include car pooling, rapid mass-transit systems, staggered or flexible work hours, and road pricing, a system whereby motorists pay a certain amount for the time they use a highway.

　　It seems that we need a new, major thrust to deal with the traffic problems of the next 20 years. There has to be a big change.

According to Larson, to redress the traffic problem, _____.

• A.car pooling must be studied
• B.rapid mass transit system must be introduced
• C.flexible work hours must be experimented
• D.overall strategies must be coordinated