Britain’s seed(种子) bank, the only one in the world aiming to collect all of the planet’s wild plant species, has reached its goal of banking 10 percent by 2010.
The Millennium Seed Bank Project, run by Kew Gardens—one of the oldest botanical(植物的)  gardens—will officially place the 24,200th species on Thursday, a pink, wild banana from China.
More than 50 countries are now on board with Kew's giant task but vast places of the globe, including India and Brazil, still need to join in and donate seeds, director Paul Smith said.                                                                                                                                                            
The seed bank is one of the largest and most diverse(多样的) in the world with more than 1.5 billion seeds. Its goal is to help protect the planet’s bio-diversity during a time of climate change.
The wild banana seed is under threat of extinction(灭绝) in southwest China from agricultural development. It is a vital food source for Asian elephants and important for growing bananas for human eating.
Stored at minus-20 degrees centigrade, so they can last for thousands of years, the seeds await the day that scientists hope never comes—when the species no longer exist in the wild.
It is a race against time, Smith said, because in the last ten years alone, 20 plants held in the bank have already been wiped out in the wild. He estimates that between a third and a quarter will become extinct this century.
"It is pressing and it is happening now. An area, the size of England, is cleared of primary vegetation（植被）every year." Smith said.
Because most of the world's food and medicines come from nature, protecting wild plant species is quite important, scientists say. There are already many other seed banks safeguarding food crops, which only account for 0.6 percent of plant diversity.
For Kew's next goal—to collect a quarter of wild varieties（种类）by 2020—the botanists need 10 million pounds a year, or a further 100 million pounds on top of the 40 million they have already been granted.
What’s the final purpose of the Britain’s seed bank?

A．To collect enough money for the project.	B．To safeguard food crops.
C．To protect wild plants from extinction.	D．To help scientists study wild plants.

We can learn from the passage that _______.

A．the seeds in the bank can be used now and then all over the world

B．India and Brazil haven’t joined in the Seed Bank Project at present

C．there is only one seed bank in the world at present

D．the wild plants in places like India and China will never die out

What does the underlined word “it” in paragraph 7 refer to?

A．The extinction of plant species.

B．The Millennium Seed Bank Project.

C．Britain’s seed bank.

D．Kew Gardens’ next goal.

Which of the following isn’t spoken about in the passage?

A．The global partnership of collecting wild plant species.

B．The temperature condition of the wild plant species in the bank.

C．The government’s support for the seed bank project by giving money.

D．Scientists’ concern on the extinct wild plant species.