21. Which of the following is used for modulation and demodulation ?

1. 1. Modem

   
   
   

   2. Protocols

   
   
   

   3. Gateway

   
   
   

   4. Multiplexer

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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22. Which of the following is called small single site network ?

1. 1. LAN

   
   
   

   2. DSL

   
   
   

   3. RAM

   
   
   

   4. USB

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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23. A (n) ...... area is a small group of computers and peripherals linked together in a small geographic area.

1. 1. MAN

   
   
   

   2. PAN

   
   
   

   3. CAN

   
   
   

   4. LAN

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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24. Switches work on which OSI layer ?

1. 1. Data link layer

   
   
   

   2. Physical layer

   
   
   

   3. Transport layer

   
   
   

   4. Network layer

   
   
   

   5. Application layer

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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25. The ........ enables you computer to connect to other computer.

1. 1. Video card

   
   
   

   2. Sound card

   
   
   

   3. Network Interface Card (NIC)

   
   
   

   4. Controller card

   
   
   

   5. None of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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