Answer:Disk
Step-by-step explanation:Disk is the storage device in which data can be rewritten and stored.They work in the computer system internally as well as externally as per the requirement
To evaluate the monitor disk performance and disk subsystem performance, it is checked whether the particular part of the computer system is working along with rest of the parts . If the working of the part is not along with other components then there will be a reduction in the performance of the system , as to keep that part on the track.
Disk is responsible for this tracking and pacing system.