A、10. B、4. C、1. D、50. B新闻中有两处提到，到了21世纪50年代，全球气温平均来说会上升4度，故正确答案是B项。注意上升10度也在新闻中提到，但只是发生在北极和非洲(Arctic and Africa)。

A new study on climate change says a disastrous 4-degree rise in global temperature is increasingly likely to occur within many people’s lifetimes. The studies have been adopted by one of the world’s leading research bodies monitoring climate change, the Hadley Centre in Britain.
    This latest prediction from the Hadley Centre brings the prospect of destructive change much closer. He challenges the assumption that severe warming is a threat only for future generations. A four degree average temperature rise by the 2050s would bring increases of 10 degrees or more in some areas such as the Arctic and Africa. It could mean a sharp decline in rainfall in some areas, flooding in others and disappearance of about half of all the world’s animal and plant species.
1. How many temperatures are expected to rise globally by the 2050s?
2. What is the result of the temperature rise by the 2050s?