【正确答案】 C

【答案解析】[听力原文] 25-27
Researchers in Australia say a group of proteins produced in the human immune system-when infected with malaria—could help lead to the creation of a malaria vaccine．Scientists at Melbourne's Walter and Eliza Hall Institute made the breakthrough．
For decades，scientists around the world have hunted for a vaccine against malaria，which claims one million lives annually(25)．
The mosquito-borne disease(26) kills a child every 30 seconds，with communities in Africa most at risk．
Malaria is caused by a complex parasite that makes it hard to target with a vaccine．
Researchers at the Walter and Eliza Hall Institute in Melbourne say the disease has evolved to thwart the body's natural defenses．
Australian scientists at the institute，however，are optimistic that a vaccine can be created because people living in malaria hotspots eventually build up some immunity against the disease．
The institute has scoured the results of international studies to find antigens-substances that provoke an immune response in the body-that could be a potent weapon against malaria．They have found a protein produced by malaria parasites that does just that．
Dr．James Beeson says a successful vaccine would stimulate the body's defenses to stop the malaria parasite．
"The basis of the vaccine would be trying to speed up what the immune system does naturally in areas where malaria occurs，"he noted．"You see children getting many episodes of malaria and gradually building up their immune response．What the vaccine would aim to do is achieve that in a much more rapid process rather than losing many people's lives and people experiencing a lot of illness before they develop immunity．"
Researchers in Melbourne hope to isolate the most effective compounds for use in a potential vaccine．
While the researchers are encouraged by their findings so far，they caution that more clinical experiments are needed and a vaccine could be at least 10 years away．
The World Health Organization says malaria is both preventable and curable．About half of the world's population is at risk of the disease。particularly those living in poorer countries．
Most fatalities occur in sub-Saharan Africa(27)，but parts of Asia，Europe，Latin America and the Middle East are also affected．
考查细节及词义理解。报道中说疟疾"claims one million lives annually"，意为“每年令一百万人死亡”。
[名师点津]
1．malaria：疟疾，经按蚊叮咬而感染疟原虫所引起的虫媒传染病。疟疾是由疟原虫引起的寄生病，于夏秋季发病较多。在热带及亚热带地区一年四季都可以发病，并且容易流行。
2．vaccine：疫苗。
3．immune system：免疫系统。
4．claim：(灾难等)使失踪或死亡。
5．scour：(彻底地)搜寻。
6．antigens：抗原类。