在人体中,EPA 和DHA 均是由( )转化得到。
A. 亚油酸
B. α-亚麻酸
C. 花生四烯酸
D. α-亚油酸
下列哪些方法不能有效解决乳糖不耐受现象?()
A. 少量多次摄入乳制品
B. 外援补充乳糖酶
C. 挑选“无乳糖”或“低乳糖”牛奶食用
D. 酸奶、奶酪
Choose the wrong one in following sentences.
A. Human activities have no impact on marine environment.
B. For the benefits of mankind, we should protect the marine environment.
C. Let nature take its course when an oil spillage happens.
D. The international conventions has regulated procedures about oil spillage.
Fire is a chemical reaction involving ________.
A. heat
B. fuel
C. air
D. all the above
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