161. Pollution of big cities can be controlled to large extent by

1. 1. Wide roads and factories away from city

   
   
   

   2. Cleanliness drive and proper use of pesticides

   
   
   

   3. Proper sewage and proper exit of chemicals from factories

   
   
   

   4. All of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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162. What is the main cause for the extinction of some species in tropical forest ?

1. 1. Deforestation

   
   
   

   2. Afforestation

   
   
   

   3. Pollution

   
   
   

   4. Soil erosion

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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163. In India, we find mangoes with different flavours, colours, fibre-content, sugar content and even shelf-life. The large variation is an account of

1. 1. Species diversity

   
   
   

   2. Induced mutations

   
   
   

   3. Genetic diversity

   
   
   

   4. Hybridization

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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164. The following pollutant is not contained in the vehicular exhaust emissions

1. 1. Lead

   
   
   

   2. Ammonia

   
   
   

   3. Carbon monoxide

   
   
   

   4. Particulate matter

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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165. The ecological foot print is a measure of ecological inpact of
     1. comsumption of food, forest products and other resources
     2. deforestation
     3. land use for roads, buildings, power plants and garbage dumps.

1. 1. 1 and 3

   
   
   

   2. 2 only

   
   
   

   3. 1, 2, and 3

   
   
   

   4. 3 only

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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