Britain is facing a 【C1】______ rise in its rat population 【C2】______ growing numbers of people leave fast food scraps in the street, an environment group warned. Keep Britain Tidy said the rodents were 【C3】______ their traditional haunts underground and were roaming the streets, enticed 【C4】______ discarded remnants of burgers, pizzas and crisps. 'The rat population is 【C5】______ the rise and soon it' 11 be as common to see a rodent on our street 【C6】______ it is to see a dog or a cat,' said group Director, Sue Nelson. The practice of dumping fast food fitter and scraps on the street 【C7】______ in the trash—with young men the worst offenders—was behind the rise. 【C8】______ to the National Rodent Survey in 2001, Britain's rat population has grown by nearly one quarter since 1998 and is now 【C9】______ at 60 million, two million more than the 【C10】______ population. On 【C11】______ a rat can give 【C12】______ every 24-28 days and just a single pair of rats can 【C13】______ a colony of 2,000 a year. Around 200 Britons a year 【C14】______ Weft's Disease—an infection which can 【C15】______ kidney or liver 【C16】______ and eventually 【C17】______ and which is carried in rat's urine. To 【C18】______ the issue, Keep Britain Tidy launched a cinema 【C19】______ entitled 'How Close do You Want Them to Get?' The ad culminates in a shocking image of a young woman sleeping in a bed of rats-echoing the nightmare scenario from James Herbert' s classic horror tale The Rats, in which mutant rodents begin to prey 【C20】______ humans.【C1】A．highB．sharpC．steepD．slight