Answer:
Thrashing :- It is a situation when the system most of it's time is handling page faults, but the actual work done by CPU is very less.
Thrashing is caused by when a process is allocated too few number of frames, then there will be continuous page faults.The actual Utilization of CPU is very less.
Thrashing detection can be done by the system by determining the CPU Utilization as compared to degree of multi programming if it comes out to be less then there is thrashing.
Thrashing can be eliminated by decreasing the Degree of multi programming.