Within the System Development Life Cycle (SDLC), which activity is most characteristic of the maintenance phase after deployment and change requests—establishing requirements, conducting analysis, or testing modified programs?

Introduction / Context:
After a system goes live, it enters maintenance—corrective fixes, adaptive changes, perfective enhancements, and preventive updates. Each change must be controlled, implemented, and verified to preserve stability and service levels. This question pinpoints the activity central to maintenance work products.

Given Data / Assumptions:

• System is already in production.
• Change requests flow through change management.
• Quality assurance continues for each update.

Concept / Approach:

While small-scale analysis and mini-requirements exist for each change, the signature activity of maintenance is testing modified programs (unit, integration, regression, and user acceptance). This ensures that bug fixes or enhancements do not break existing functionality and that the system remains compliant and reliable.

Step-by-Step Solution:

Verification / Alternative check:

ITIL/DevOps practices emphasize continuous testing and regression checks on maintenance releases and hotfixes.

Why Other Options Are Wrong:

“System analysis” and “requirements established” are primary development-phase activities; in maintenance they appear in narrow scope but are not the hallmark.

“All of the above” overstates maintenance scope.

Common Pitfalls:

Skipping regression tests for “small” fixes; even minor changes can have wide impact without automated tests and rollback plans.

Final Answer:

Programs are tested