What kind of toothbrush does the woman buy（）

A. Scientists have managed to persuade industries to take measures to reduce emissions of gases into the atmosphere.
B. There is no general agreement on the causes and effects of acid rain yet.
C. Special glasshouses are set up in order to investigate the effects of air pollution on plants.
D. Ozone is mainly emitted by the oil refining industry.

A. Ozone is not always associated with acid rain.
B. Cold weather would make the effects of pollution worse.
C. Many industries are unwilling to accept responsibility for air pollution.
D. Plants in warm weather are dying faster.