Britain is facing a sharp rise in its rat population as growing numbers of people leave what they cannot finish of the fast food in the street, an environment group warned .Keep Britain Tidy said the rats were stopping their traditional hunts underground and were running across the streets, invited by burgers, pizzas and crisps left behind by man. "The rat population is on the rise and soon it'll be as common to see a rat on our street as it is to see a dog or a cat," said group Director, Sue Nelson. The practice of spreading fast food litter and scraps on the street rather than in the dustbin--with young men the worst group--was behind the rise. According to the National Rodent Survey in 2005, Britain's rat population has grown by nearly one quarter since 2000 and is now estimated at 60 million, two million more than the human population. On average a rat can give birth every 24-28 days and just a single pair of rats can produce a family of 2,000 a year. Around 200 people a year get Weil's Disease -an infection which can lead to liver or kidney failure and eventually death and which is carried in rats' waste. To attract people's attention to the problem, Keep Britain Tidy produced a cinema ad with a title "How close do you want them to get?" The ad gave a shocking image of a young woman sleeping in a bed of rats--reminding people of the terrible scene from James Herbert's classic horror tale The Rats, in which rats begin to hunt for humans. By writing the passage, the author tries to    _   .
close some of the burger and pizza restaurants draw the public attention to the problem of rats prevent the rats from growing up making an advertisement for the classic horror tale The Rats