Explanation
Correct Answer: (a) Hard disk
Detailed Explanation
In computer architecture, interrupt priority is generally assigned based on the speed of the device, data transfer rate, and the urgency of data retrieval to prevent data loss.
The Speed-Priority Rule: High-speed hardware devices with large data transfer rates require faster service from the CPU. If a fast device is not serviced quickly, its data buffer might overflow, leading to severe data loss. Therefore:
Data Transfer Speed∝Interrupt Priority Level
Comparing the Given Devices:
Hard Disk: It is a high-speed secondary storage device with a high data transfer rate. It requires immediate attention from the CPU during read/write operations to avoid latency or data corruption.
Floppy Disk: It operates significantly slower than a modern hard disk, thus requiring a lower priority.
Keyboard & Printer: These are slow input/output (I/O) peripheral devices. Human typing speed or mechanical printing processes are incredibly slow compared to CPU processing cycles, so they are assigned lower priority levels.
Priority Hierarchy Chart:
\text{Hard disk} > \text{Floppy disk} > \text{Printer} > \text{Keyboard}
