Arrange the evolution of operating systems in chronological order: A.…

Concept

When an exam asks for the evolution of operating-system types, it may use a pedagogical progression of increasing interaction, concurrency, and response requirements rather than the first deployment date of every technology.

These categories overlap in real history; therefore, the order here is the conventional progression accepted for this UGC NET previous-year question.

Application

1. Batch processing groups jobs and runs them without direct user interaction; it is the starting stage in this convention.

2. Single-user single-tasking represents one user working on one active task and is placed after batch processing in the exam sequence.

3. Multiprocessing adds the use of multiple processors for concurrent execution and is placed next in the same sequence.

4. Real-time operating systems emphasize bounded, deadline-sensitive responses and occupy the final position in this exam convention.

Cross-check

The exact UGC NET Paper 1 item held on 8 January 2025, Shift 2, is keyed as C → D → B → A. This confirms the exam-accepted option, while the sequence should not be read as a claim that multiprocessing or real-time systems had no early historical implementations.

Therefore, for this previous-year question, the accepted chronological order is C, D, B, A.