Passage Four Even plants can run a fever, especially when they’re under attack by insects or disease. But unlike humans, plants can have their temperature taken from 3,000 feet away——straight up. A decade ago, adapting the infrared (红外线) scanning technology developed for military purposes and other satellites, physicist Stephen Paley came up with a quick way to take the temperature of crops to determine which ones are under stress. The goal was to let farmers pre-cisely target pesticide (杀虫剂) spraying rather than rain poison on a whole field, which in- variably includes plants that don’t have pest (害虫) problems. Even better, Paley’s Remote Scanning Services Company could detect crop problems be- fore they became visible to the eye. Mounted on a plane flown at 3,000 feet at night, an infra- red scanner measured the heat emitted by crops. The data were transformed into a color-code map showing where plants were running" fevers". Farmers could then spot-spray, using 50 to 70 percent less pesticide than they otherwise would. The bad news is that Paley’s company closed down in 1984, after only three years. Farmers resisted the new technology and long-term backers were hard to find. But with the renewed concern about pesticides on produce, and refinements in infrared scanning, Paley hopes to get back into operation. Agriculture experts have no doubt the technology works. "This technique can be used on 75 percent of agricultural land in the United States", says George Oerther of Texas A&M. Ray Jackson, who recently retired from the Department of Agricultrue, thinks re- mote infrared crop scanning could be adopted by the end of the decade. But only if Paley finds the financial backing which he failed to obtain 10 years ago. The application of infrared scanning technolgy to agriculture met with some difficulties due to （）

A. the lack of official support
B. its high cost
C. its failure to help increase production
D. the lack of financial support