Just seven years ago, the Jarvik-7 artificial heart was being cheered as the model of human creativeness. The sight of Barney Clark-alive and conscious after trading his diseased heart for a metal-and-plastic pump-convinced the press, the public and many doctors that the future had arrived. It hadn't. After monitoring production of the Jarvik-7, and reviewing its effects on the 150 or so patients (most of whom got the device as a temporary measure) the U.S Food and Drug Administration concluded that the machine was doing more to endanger lives than to save them. Last week the agency cancelled its earlier approval, effectively banning the device.
　　
　　The recall may hurt Symbion Inc, maker of the Jarvik-7, but it wont end the request for an artificial heart. One problem with the banned model is that the tubes connecting it to an external power source created a passage for infection. Inventors are now working on new devices that would be fully placed, along with a tiny power pack, in the patient's chest. The first samply products aren't expected for another 10 or 20 years. But some people are already worrying that they'll work-and that America's overextended health-care programs will lose a precious $2.5 billion to $5 billion a year providing them for a relatively few dying patients. If such expenditures cut into funding for more basic care, the net effect could actually be a decline in the nation's health.
　　
　16. According to the passage the Jarvik-7artificial heart proved to be _______.
　　 [A] a technical failure
　　 [B] a technical wonder
　　 [C] a good life-saver
　　 [D] an effective means to treat heart disease

　17. From the passage we know that Symbion Inc ______.
　　 [A] has been banned by the government from producing artificial hearts
　　 [B] will review the effects of artificial hearts before designing new models
　　 [C] may continue to work on new models of reliable artificial hearts
　　 [D] can make new models of artificial hearts available on the market in 1O to 20 years

　18. The new models of artificial hearts are expected ______.
　　 [A] to have a working life of 10 or 20 years
　　 [B] to be set fully in the patient's chest
　　 [C] to be equipped with an external power source
　　 [D] to create a new passage for infection

　19. The word "them" in Line 7, Para. 2 refers to _____.
　　 [A] doctors who treat heart diseases
　　 [B] makers of artificial hearts
　　 [C] America's health-care programs
　　 [D] New model of artificial hearts

　20. Some people feel that ______.
　　 [A] artificial hearts are seldom effective
　　 [B] the country should not spend so much money on artificial hearts
　　 [C] the country is not spending enough money on artificial hearts
　　 [D] America's health-care programs are not doing enough for the nation's health