ANS:B - Sequential

Long-Long time ago when we are small, we use cassettes. This is a box like a thing which contains songs or sometimes movies.

Any one who did operate this cassette, know that we can't go directly from song no 1 to song no 10. We have to go to 2, 3, 4, 5, 6, 7, 8, and 9 songs to rich 10th song.

Cassettes are built like that. The cassette has information in a long tread this tread is move forward and the information is read by!