556. Which of the following fuels causes minimum environmental pollution ?

1. 1. Diesel

   
   
   

   2. Kerosene

   
   
   

   3. Hydrogen

   
   
   

   4. Coal

   
   
   

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   Hydrogen

   Correct Option: C

   Hydrogen

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557. Lactose is present in

1. 1. grapes

   
   
   

   2. milk

   
   
   

   3. lime

   
   
   

   4. vinegar

   
   
   

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   milk

   Correct Option: B

   milk

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558. Which of the following has no blood, but respires ?

1. 1. Fish

   
   
   

   2. Earthworm

   
   
   

   3. Hydra

   
   
   

   4. Cockroach

   
   
   

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   Hydra

   Correct Option: C

   Hydra

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559. Prawn heart carries

1. 1. no blood

   
   
   

   2. deoxygenated blood

   
   
   

   3. oxygenated blood
      

   
   
   

   4. mixed blood

   
   
   

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   oxygenated blood

   Correct Option: C

   oxygenated blood

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560. In our body, antibodies are formed against pathogens in

1. 1. liver by RBC

   
   
   

   2. blood by platelets

   
   
   

   3. brain by macrophages

   
   
   

   4. thymus by lymphocytes

   
   
   

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   thymus by lymphocytes

   Correct Option: D

   thymus by lymphocytes

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