Concept:The physical components of a computer system are the tangible parts you can see and touch.
Explanation:Hardware refers to all the physical parts of a computer, such as the monitor, keyboard, mouse, motherboard, RAM, and hard disk drive.
These components are concrete and can be handled physically.
Software, on the other hand, is a set of instructions or programs, not a physical object.
A compact disk and the system unit are only specific examples of hardware, not the general term for all physical components.
Therefore, the correct general term is hardware.
Answer:B. hardware