A-A+
Pollution in water is noticed ______.A．when po
问题详情
Pollution in water is noticed ______.
A．when poisons are poured into water
B．when a great many fish and birds die
C．when the first organisms are affected
D．as soon as the balance of nature is destroyed请帮忙给出正确答案和分析，谢谢！
参考答案
正确答案：B
解析：细节题。文章第二段提到“it is not until dead fish and water birds are found at the river's edge or on the sea shore that people realize what is happening”，意思是“人们只有在湖畔及海边发现死鱼、死鸟时，才意识到污染的存在”，所以答案是[B]。
