题目

Have you seen koalas (考拉) in a zoo? They are very cute. The koala is a small bear-like, tree-dwelling animal, which averages about 9 kilograms in weight. Its fur is thick and usually ash gray. They come from Australia. They do not come from any other place. Today koalas are mainly found in Queensland, New South Wales, Victoria and South Australia. People in Australia want to protect them. Now there are about 100,000 koalas in Australia. But there are fewer and fewer of them all the time. Some koalas are getting sick. The sickness makes them not able to see. It also makes it hard for them t已知的图像如图所示 ,则函数的图像是（   ）