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The Search-for-Lost-Birds list has come to public attention recently. It lists ten kinds of birds that have not been seen in the wild for at least fifteen years. The list is calling on people to search for the rarest (最珍稀的) birds on Earth.
There could be several reasons for the long disappearances of the birds on the list. Maybe there have been no studies in areas where they live. Maybe people don’t know where or how to find them. Maybe there are changes to their natural homes because of human activities.
This year, four expeditions (考察队) are planning to find eight kinds of birds. If any of these lost birds are found, ways can be found to protect them and help their populations grow. This has happened with birds like the Madagascar pochard. The number of this once-lost kind of bird is now increasing.
1．How many kinds of birds are on the Search-for-Lost-Birds list?| A．Four. | B．Eight. | C．Ten. | D．Fifteen. |
| A．Changes of the living areas of the birds. | B．Suggestions on how to protect the birds. |
| C．Reasons for the disappearances of the birds. | D．Steps of building natural homes for the birds. |
| A．It has not been found till now. | B．It has a larger population than before. |
| C．It needs to live close to humans. | D．It provides protection for other birds. |
| A．Ways to Raise Rare Birds | B．Bird-lovers Around the World |
| C．Searches for the Lost Birds | D．Stories About Birds in the Wild |
同类型试题
y = sin x， x∈R， y∈[–1，1]，周期为2π，函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x， x∈[–1，1]， y∈[–π/2，π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
y = sin x， x∈R， y∈[–1，1]，周期为2π，函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x， x∈[–1，1]， y∈[–π/2，π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
