Weallhaveanideaaboutthecommontypesofenvironmentalproblems．However，lightpollutionmaybeanewtermtomanyofus．But，thefactis，itdoesaffectmankind，otherlivingformsandtheenvironmentasawhole．Whatislightpollutio

　　We all have an idea about the common types of environmental problems．However，light pollution may be a new term to many of us．But，the fact is，it does affect mankind，other living forms and the environment as a whole．

　　What is light pollution？It presents all forms of misused man-made light．The obvious cause of light pollution is the use of outdoor lighting products improperly．It can be office lighting，car headlights，station lights，streetlights and many more．

　　Light pollution is harmful to both animals and plants．Upon studies，it is found that obvious effects are observed in the behaviour of nocturnal animals．Needless to mention，bright light at night makes it difficult for these animals to hunt，wander and perform their regular activities．Light pollution is directly or indirectly responsible for causing several diseases．Its effects are related to disturbance in the physical rhythm．It contributes to risks of developing cancerous cells．So，it's nothing less than a threat to human health．

　　You have already seen the negative effects of light pollution on animals and human health．Apart from this，the actual cost of misused light is about millions of dollars every year．It also leads to the release of greenhouse gases and global warming．After all，fuels are used for producing electricity．

　　While outdoor lighting and using man-made lighting products are part of our modern lifestyle，some simple ways will surely help in reducing light pollution．For example，while installing outdoor lighting，make sure that they are pointed downwards．Also，use only the required lighting equipment for both home and offices．Believe it or not，many people living in the urban areas cannot view clear sky and stars at night．Let's contribute our part in reducing the pollution．

　　32．What can we learn about light pollution？___

　　A．It is a negative fruit of light technology．

　　B．It has no effect on plants

　　C．It contributes to most cancers．

　　D