“The British government will offer ￡1,000,000 to anyone who can solve the world’s biggest problem—whatever it might be,” said Prime Minister(首相) David Cameron at a science conference. In an unusual competition, the Government will ask people to find out the greatest challenge(挑战) today, such as finding a replacement(替代) for oil, producing low cost food or curing AIDS/HIV. When the toughest problem has been decided, the Prime Minister will give away ￡1,000,000 to the person who successfully works out the answer. The competition follows the example of the Longitude Prize started by the government in 1714, which offered ￡20,000 (worth ￡6,000,000 today) to anyone who could discover how far east or west ships had sailed. Sailors could work out their location north and south, and were able to decide their local time from the sun. However, they needed to know the time at a reference(参照) point in order to find out how far they had travelled east or west. Many people thought the problem was impossible to solve, but the prize was finally won by John Harrison, an ordinary worker. He did this by designing a clock that kept accurate(准确的) time at sea and made it possible for sailors to work out their location.        Almost exactly 300 years on, Mr Cameron will have a group of scientists collect suggestions and draw up a short list of problems facing the world. He will then start a race to solve the most difficult problem. A government officer said, “We want people to think big: what does the world need and how can we achieve that? We are looking for the next penicillin(青霉素), airplane or World Wide Web. Something that is going to really change what we do and how we live our lives—sending us ahead in the global race. ”According to Mr Cameron, it is important to “encourage new ideas” and “attract back the best and the brightest” to Britain.
The British government promises ￡1,000,000 to any person who .

A．can solve the biggest challenge facing the world

B．can find how the next penicillin works on illnesses

C．can think of the most difficult problem in the world

D．can help the Prime Minister run his government better

The Longitude Prize is mentioned mainly to .

A．explain why the government set up the prize in 1714

B．show John Harrison was a great success as an inventor

C．show that the government is very grateful to John Harrison

D．explain what gave Mr Cameron the idea of starting the competition

We can infer(推断) from Paragraphs 4 and 5 that .

A．ships no longer get lost at sea with Harrison’s invention

B．clocks on ships kept good time before Harrison’s invention

C．sailors found it hard to work out their location north and south

D．the sailing industry was very important in Britain around the 1700s

Which of the following is true according to the text?

A．John Harrison was sure that he would win the prize.

B．The million pound prize will go to a British scientist.

C．The British government pays special attention to the nation’s creativity.

D．A replacement for oil is considered as the toughest problem by the scientists.