How many states can be processed in an operating system?

Concept: In an operating system, a process is a program in execution, and the OS tracks its progress using a process state model — a fixed set of named states the process moves between as it competes for the CPU and waits for events. The number of states depends on the model; the standard textbook (basic) model defines a specific count, while extended models add more.

Standard (basic) model: The widely taught textbook model (e.g. Silberschatz) defines five states a process passes through:

1. New: the process is being created or loaded into primary memory.

2. Ready: the process is in main memory and waiting to be assigned to the CPU.

3. Running: instructions are being executed by the CPU.

4. Waiting (Blocked): the process is waiting for an event such as an I/O operation to complete.

5. Terminated (Exit): the process has finished execution and is being removed from memory.

Cross-check / extension (suspended states): Some advanced models extend this to a seven-state model by adding Suspend-Ready and Suspend-Blocked (Suspend-Wait), which describe processes swapped out of main memory to disk by the medium-term scheduler. These are refinements of the basic model, not separate from it. Because the offered choices are 2, 3, 4 and 5, the answer that matches the standard basic process state diagram is 5.