Occurs when the system finds itself spending so much time swapping pages into and out from memory that little time is left for useful work.

a. spooling
b. thrashing
c. an interrupt
d. a polling signal

Option b is the correct answer for the above question.

Explanation:

Thrashing occurs when the virtual memory of the computer is more used. It is because the system does not have more memory. That's why the virtual memory is busy in the paging or other work of the operating system and there is no memory left for the other useful work of the system and then Thrashing occurs.

The question statement states the same which is described above and this is the cause when thrashing occurs. Hence the b option is correct. while other is not because--

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