System Capability Which capability is required for a system to execute more than one program at a time?

Introduction / Context:
Running multiple programs concurrently requires operating system support and appropriate hardware scheduling. The umbrella term for this system ability is multitasking, which coordinates CPU time among processes/threads.

Given Data / Assumptions:

• Time-sliced CPU with a scheduler.
• Processes or threads managed by the kernel.
• Possibly a single CPU (preemptive multitasking) or multiple CPUs (true parallelism).

Concept / Approach:
Distinguish features (applications) from system capabilities. Word processing and compiling are workloads, not enablers. Virtual memory is helpful but not strictly required to run more than one task; it provides address space isolation and over-commit handling. The defining capability is multitasking.

Step-by-Step Solution:
Identify OS services: process creation, scheduling, context switching.Assess whether multiple tasks can be runnable/ready simultaneously.Conclude that multitasking is the prerequisite capability.

Verification / Alternative check:
Observe a system monitor while multiple applications run; CPU time is shared among them via context switches—clear evidence of multitasking.

Why Other Options Are Wrong:
Word processing and compiling (Options A/B) are application types, not OS capabilities.Virtual memory (Option C) enhances protection/isolation but is not the sole requirement for simultaneity.

Common Pitfalls:

• Assuming virtual memory equals multitasking; they address different concerns.
• Confusing multithreading (within one process) with multitasking (multiple processes).

Final Answer:
Multitasking.