更多"Recent research had claimed that an"的相关试题:
[单项选择] Recent research had claimed that an excess of positive ions in the air could have an ill effect on people’’s physical or psychological health. What are positive ions Well, the air is full of ions, electrically charged particles, and generally there is a rough balance. If the balance becomes disturbed and a larger proportion of positive ions are found. This happens naturally before thunderstorms, earthquakes or when winds such as the Mistral, Foehn, Hamsin or Sharav are blowing in certain countries. Or it can be caused by a build-up of static electricity indoors from carpets or clothing made of man-made fibers, or from TV sets, duplicators or computer display screens.
When a large number of positive ions are present in the air many people experience unpleasant effects such as headaches, fatigue, irritability, and some particularly sensitive people suffer nausea or even mental disturbance. Animals are also found to be affected, particularly before earth- quakes; snakes have bee
A. They think they are mad.
B. They feel very tired.
C. They become violently sick.
D. They are too tired to do anything.
