题目内容：

Seeds on Ice

Close to the North Pole，remote and rocky Plateau Mountain in the Norwegian archipelago of

Svalbard seems an unlikely spot for any global effort to safeguard agriculture. In this cold and deserted environment，no grains，no gardens，no trees can grow. Yet at the end of a 130-meter-long tunnel cut out of solid stone is a room filled with humanity’s most precious treasure, the largest and most diverse seed collection—more than a half-billion seeds.

A quiet rescue mission is under way. With growing evidence that unchecked climate change-will seriously affect food production and threaten the diversity （多样性） of crops around the world，the Svalbard Global Seed Vault （地窖） represents a major step towards ensuring the preservation （贮藏） of hundreds of thousands of crop varieties. This is a seed collection, but more importantly, it is a collection of the traits found within the seeds：the genes that give one variety resistance to a particular pest and another variety tolerance for hot，dry weather.

Few people will ever see or come into contact with the contents of this vault. In sealed boxes，behind multiple locked doors，monitored by electronic security systems, enveloped in below—zero temperatures, and surrounded by tons of rock, hundreds of millions of seeds are protected in their mountain fortress. Frozen in such conditions inside the mountain, seeds of most major crops will remain viable for hundreds of years, or longer. Seeds of some are capable of retaining （保留） their ability to grow for thousands of years.

Everyone can look back now and say that the Seed Vault was a good and obvious idea, and that of course the Norwegian government should have approved and funded it. But back in 2004, when the Seed Vault was proposed, it was viewed as a crazy，impractical, and expensive idea.

We knew that nothing would provide a definite guarantee. But we were tired，fed up，and frankly scared of the steady, greater losses of crop diversity. The Seed Vault was built by optimists who wanted to do something to preserve options so that humanity and its crops might be better prepared for change. If it simply resupplied seed gene banks with samples those gene banks had lost, this would repay our efforts.

The Seed Vault is about hope and commitrnent - about what can be done if countries come together and work cooperatively to accomplish something significant，long-lasting，and worthy of who we are and wish to be.

1.According to the passage, the Seed Vault is ___________.

A.a tunnel where the collected seeds are displayed

B.a stone room that contains the seeds of endangered crops

C.a seed gene bank that stores diverse seeds for future agriculture

D.a lab where researchers study how to maintain the diversity of crops

2.The underlined word“viable”in Paragraph 3 probably means ________.

A.mature B.clean

C.alive D.valuable

3.Paragraph 3 mainly tells us __________.

A.how the seeds are preserved B.where people keep the seeds

C.why the seeds are protected D.what people do to study the seeds

4.We can know from the passage that _________.

A.the Seed Vault offers a solution to climate change

B.most countries took part in rescuing the seed varieties

C.the Seed Vault guarantees to prevent the loss of crop diversity

D.many people originally considered building the Seed Vault unwise