Answer should be (D) Higher priority interrupt levels are assigned to requests which, if delayed or interrupted,could have serious consequences. Devices with high speed transfer such as magnetic disks are given high priority, and slow devices such as keyboard receive low priority. We know that mouse pointer movements are more frequent than keyboard ticks. So its obvious that its data transfer rate is higher than keyboard. Delaying a CPU temperature sensor could have serious consequences, overheat can damage CPU circuitry. From the above information we can conclude that priorities are-
CPU temperature sensor > Hard Disk > Mouse > Keyboard