Sentence Correction
试题详情
题目：
Often visible as smog, ozone is formed in the atmosphere from hydrocarbons and nitrogen oxides, two major pollutants emitted by automobiles, react with sunlight.
选项:
A、 ozone is formed in the atmosphere from
B、 ozone is formed in the atmosphere when
C、 ozone is formed in the atmosphere, and when
D、 ozone, formed in the atmosphere when
E、 ozone, formed in the atmosphere from
答案:
B
