题目内容：

Native to America, the cane toad (癞蛤蟆) was introduced to Northern Queensland 70 years ago to control sugarcane beetles (甘蔗害虫). The toads failed in that duty but spread across Queensland and into neighboring northern areas.

Now it calmly invades(侵略) the stats of Western Australia and New South Wales ( NSW). NSW wildlife experts fear the amphibians － which have poisonous backs that kill hungry predators (食肉动物) 一will have a terrible effect on native animals.

Those fears may be about to be realized. Australia’s leading government research body, the Commonwealth Science and Industry Research Organization (CSIRO), forecasts that a rise in average temperatures will make NSW an ideal living place for the cane toads.

Tony Robinson, head of CSIRO’s Wildlife, Pests, and Diseases Program, said climate change is increasing the amount of suitable living place for the cane toads.

“With climate change, the cane toads might go down as far as Sydney and some areas of Western Australia,” Robinson said.

Recent estimates put the pace of the toads’ westward march at nearly 17 miles (27 kilometers) a year and slightly slower from north to south.

“More southerly (南部的) cities, such as Melbourne and Adelaide, would likely remain too cold and dry to ever suit the toads,” Robinson noted, “but Perth could expect cane toads in five years’ time.”

Sydney could see their arrival in the next 20 years.

Robinson said there is no method that will keep the toads under control.

The cane toads already cover at least half of Queensland and most of the northern country. The toads are believed to number in the billions.

A Venezuelan virus was tried in the 1990s but had to be given up after it was found to also kill native frog species. Scientists and governmental bodies believe a national approach is needed.

The main threat the toads cause to species such as dingoes, and crocodiles is the poison contained in glands (腺) on each of their shoulders. The poison sprays out when the toads are threatened or handled roughly. The poison is made up of 14 different chemicals.

Cane toads also compete, and usually win, the hunt for food and living space.

"”If the government and other states combine resources, I believe we can achieve a very practical biological-control research program,” Bums said.

1.Which of the following can be the best title of the passage?

A. Poison Toads Leap Across Australia

B. Strategies to Keep the Toads under Control

C. The Main Threat the Cane Toads Cause

D. Climate Favours the Spread of Cane Toads

2.It can be inferred from the passage that

A. the cane toad bites its enemy dead when it is threatened or handled rudely

B. the cane toad has already threatened the survival of all the native species

C. scientists and governmental bodies have achieved a successful biological-control program

D. the cane toad likes warm and wet weather

3.The underlined words “the amphibians” in the second paragraph mean _______.

A. hungry predators    B. sugarcane beetles

C. the cane toads    D. dingos

4.According to the passage, the cane toad is the least likely to live in ______

A. Queensland    B. Melbourne

C. Sydney    D. Perth