Choose the wrong statements.

1.'CD' is an example of optical device

2.'Floppy' is an example of magnetic device

3.'Pen drive' is an example of magnetic state device

4.'Memory Card' is an example of crystal state device

A1 & 2 only

B3 & 4 only ✓ Correct

C2 & 4 only

D2 & 3 only

Correct answer: (B) 3 & 4 only

Explanation

Statement 3 is wrong because a pen drive uses flash solid state memory, not a magnetic device.

Statement 4 is wrong because a memory card is flash storage, not a crystal state device.

Statement 1 is correct because a CD is an optical device read by laser.

Statement 2 is correct because a floppy disk is a magnetic storage device.

Flash storage keeps data in electronic cells with no moving or magnetic parts.

Optical media store data as pits and lands read by a laser beam.

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