—Why do you like playing football?
—Because it’s（）．

听力原文： Scientists believe that when the oceans were young, they contained only a trace of salt, and that the level of salinity has been going up gradually. Over the years, rains have been wearing away the reek mantle of the continent. Minerals released by these erosion have been carded to the sea by the flow of river water. This water adds several billions tons of salt to the ocean annually. There are other sources of oceanic salinity too; one source is underwater volcanic action. These eruptions occurred along the mid-ocean ridge and release great amount of salt into the sea each year. However, these sources don't increase the actual mineral composition of the water by much because the enormous chemical requirements of marine life. Oysters, clams, snails and other mollusk use salt to build shells and skeletons. Coral reefs also consume large amount of salt. Also, some salt leaves the ocean through the process of evaporation. As salts escape into the atmosphere, they go into the creation of rain drops, this is why the coast receives more rain. Salt exists in the atmosphere near the ocean, thereby attracting the increased moisture and producing rain.What does the speaker say about the ocean's level of saltiness?A．The level of saltiness in the ocean is extraordinarily high.B．The average level of salinity in the ocean is higher than that of inland lakes.C．Salt has been gradually accumulating in the ocean, which leads to a rise in oceanic salinity level.D．Salt has accumulated very quickly at the early stage of life formation, then this process gradually slow down.

A.
What
B.The
C.
B．The
D.
C．Salt
E.
D．Salt
F.

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听力原文： Iraqi security officials say a suicide car bomber struck a police checkpoint in western Ramadi today, killing at least 20 people and wounding 30 others. The top local police official said two policemen were among the dead. Ramadi is the capital of the restive al-Anbar province, which has been a stronghold of Sunni insurgency. But recently many tribes have switched sides and joined the Iraqi police and army in an attempt to expel al-Qaida in Iraq fighters from their region. Separately, reports say U. S. and Iraqi forces have moved into the southern city of Diwaniyah in an operation to stop increasing influence of Shiite militia loyal to anti-American cleric Moqtada al-Sadr.How many policemen were killed in the bombing?A．2.B．3.C．20.D．30.

A.
How
B.2.
B．3.
C．20.
D．30.

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