单项选择题

（ ）能促进小肠黏膜对钙的吸收，促进骨组织钙化。

A.维生素A
B.叶酸
C.维生素
D.膳食纤维
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单项选择题
根据以下材料，回答{TSE}题 Underground Coal Fires Coal burning deep underground in China, India and Indonesia is threatening the environment andhuman life, scientists have warned. These large-scale __________(51) blazes cause the ground temperature to heat up and kill surrounding vegetation, produce greenhouse gases and can __________(52) ignite forest fires, a panel of scientists told the annual meeting of the American Association for the Advancement of Science in Denver. The resulting__________ (53) of poisonous elements like arsenic and mercury can also pollute local water sources and soils,they warned. Coal fires are a global catastrophe, said Associate Professor Glenn Stracher of East Georgia College in Swainsboro, USA. But __________ (54) few people know about them. Coal can heat up on its own, and eventually catch fire and burn, if there is a continuous oxygen supply. The heat produced is not caused to __________ (55) and under the right combinations of sunlight and oxygen, can trigger spontaneous catching fire and burning. This can occur underground, in coal stockpiles, abandoned mines or even as coal is transported.__________ (56) fires in China consume up to 200 million tones of coal per year, delegates were told. In __________(57), the U.S. economy consumes about one billion tones of coal annually, said Stracher,.__________ (58)analysis of the likely impact of coal fires has been accepted for publication in the International Journal of Coal Ecology. __________(59) underway, coal fires can bum for decades, even centuries. In the process, they release large__________(60) of greenhouse gases, poisonous fumes and black particles into the atmosphere. The members of the panel discussed the__________(61) these fires may be having on global and regional climate change, and agreed that the underground nature of the fires makes them difficult to __________(62). Ultimately, the remote sensing and other techniques should allow scientists to __________(63)how much carbon dioxide these fires are emitting. One suggested__________ (64) of containing the fires was presented by Gary Colaizzi, of the engineering firm Goodson, which has developed a heat-resistant grout (a thin mortar used to fill cracks and crevices), which is designed to be pumped into the coal fire to__________(65) the oxygen supply. {TS}回答(51)题
A.house 
B.underground
C.sky
D.water
单项选择题
幼儿园的红红喜欢跟王老师分享她的生活，即使她表达一句完整的话需要很长时间，王老师也能很有耐心地听她讲完，并通过她的言行尝试去理解她并给予她肯定。王老师还会每天注意观察每个小朋友以了解、记录其行为、性格特点。从教师观角度，王老师是()。
A.幼儿的倾听者与观察者
B.幼儿的支持者与引导者
C.幼儿活动的合作者
D.研究者、学习者、创造者
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