The koala, cuddly symbol of a nation and one of the most beloved animals on the planet, is in crisis. Before Europeans settled A

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问题     The koala, cuddly symbol of a nation and one of the most beloved animals on the planet, is in crisis. Before Europeans settled Australia more than two centuries ago, about ten million koalas lived in a 1, 500-mile-long swath of the east coast eucalyptus forests. Hunted for their luxurious fur, koalas were brought to the edge of extinction in the southern half of their range. In the northern half, Queensland, a million were killed in 1919 alone. After the last open season in Queensland was held in 1927, only tens of thousands remained.
    Through the next half century their numbers slowly rebounded, in part due to efforts to relocate and recolonize them. Then urbanization began to take its loll. Habitat was lost, and diseases spread. With urbanization came the threat of dogs and highways. Since 1990, when about 430,000 koalas inhabited Australia, their numbers have dropped sharply. Because surveys are difficult, current population estimates vary widely— from a low of 44,000 by advocacy groups to a high of 300,000 by government agencies. More than a decade ago a survey of the Koala Coast, a 93,000-acre region in southeastern Queensland, estimated a koala population of 6,200; today there are believed to be around 2,000.
    "Koalas are getting caught in fences and dying, being killed by dogs, struck by vehicles, even dying simply because a homeowner cut down several eucalyptus trees in his backyard," says Deidre de Villiers, one of the chief koala researchers at the Queensland Department of Environment and Resource Management. De Villiers insists that koalas and humans can coexist in urban environments, if developers get on board with koala-sensitive designs, such as lower speed limits for streets, green corridors for koala movement, and, most especially, preserving every precious eucalyptus tree. Unfortunately, koalas have another problem.
    "Disease is the other huge issue," says veterinarian Jon Hanger, 42, from the Royal Society for the Prevention of Cruelty to Animals in Queensland. Hanger has discovered that as much as half of Queensland’s koala population may be affected by the sexually transmitted disease chlamydiosis. In some wild koala populations more than 50 percent of the sexually mature females are infertile. The genesis of the disease is unknown, but it manifests itself as urogenital and ocular disease and is transmitted through mating and birthing, as well as fighting among males. Unlike in humans, chlamydiosis in koalas is often fatal.
    "Koala populations that used to be vibrant and sustainable are becoming extinct," says Hanger, who puts the blame squarely on the provincial government. "Queensland has failed miserably to do anything meaningful about the decline. The federal government needs to get involved and do it properly, listing the koala as vulnerable to extinction. " Such a designation might save the last remnants of critical koala habitat, he argues. Hanger is also part of a research team developing a chlamydia vaccine.
    A recent report presented to the Australian Senate made several recommendations to save the koalas, including listing the animals as threatened and vulnerable, funding a program to monitor koala populations, mapping their habitat, and managing federal and private lands to protect the koalas. Until such measures are taken, the efforts of grassroots koala emergency squads will continue to be essential.
According to the text which one of the followings is not a reason that has caused Koala numbers decrease?

选项 A、Hunted for their luxurious fur
B、Lost of habitat
C、Spread of disease
D、Climate change

答案D

解析 本题考查考生对文中所述考拉数量减少的各种原因的理解。前四段都是在讲造成考拉数量减少的原因。第一段的第三句说到为了得到考拉昂贵的皮毛,人们对他们大肆猎捕,使得居住区域南半部分的考拉陷入灭绝的边缘,因此A选项正确。第二段第二、三两句提到由于城市化进程的影响,考拉失去了栖息之地,后面提到考拉数量急剧下滑。因此B项正确。C选项出现在文章里的两个地方,第一次出现是在第二段第三句,同样由于城市化的影响,考拉不仅失去了栖息之地,而且疾病蔓延,狗和公路对考拉的威胁也随之而来。第二次出现是在第四段,整段都在讲述衣原体病对考拉的巨大影响,因此C项也正确。D项是作者故意设置的干扰选项,是个很诱人的原因,但是全文并没有任何地方提到,因此D项错误.
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