维系蛋白质三级结构稳定的最重要的键或作用力是A．盐键 B．氢键 C．范德华力 D．疏

VII. 写作（Writing）（共2小题，计２5分）
　
A) Read the following passage, and then use your own words to give a brief summary of it in about 90 words.（10分）（答案写在答题纸上）
All thanks to the mobile phone

Dave Mill owes his life to his mobile phone. He was trying to make history by walking to the North Pole alone, without any help or support. But after 50 days of extremely bad weather, during which the temperature dropped as low as minus 30°C, Dave was forced to abandon his attempt. He had completed 185 miles of the 375-mile journey and had suffered several mishaps（不幸事故）. He had broken his sunglasses, been followed by polar bears and fallen into freezing water twice. Then, after making the decision to give up, he had some more bad luck and found himself stranded （处于困境的） on a floating piece of ice that was slowly melting.

 
The weather was too bad for any rescue attempt to be made. Dave waited for three days, hoping that conditions would improve. But the rescue planes could not land because dense fog prevented them from seeing the surface of the ice. It was a race against time.
Then he remembered his mobile phone. He marked out a runway on the ice and took a photograph with his digital camera. Then he used his phone to e-mail it to the waiting air rescue team. Using the photograph to guide him, the pilot was able to land in spite of the weather, and Dave was lifted off the ice to safety.