Modifying the software to match changes in the ever changing environment is…

Explanation: Modifying the software to match changes in the ever-changing environment is called adaptive maintenance.

• Adaptive maintenance - Changes made so the software continues to function when external conditions change (e.g., OS upgrades, new hardware, regulatory changes, integration with other systems).

• Corrective maintenance - Fixes faults and defects discovered after release; addresses bugs and errors.

• Perfective maintenance - Improves performance, usability, or adds enhancements requested by users; focuses on improvement rather than environmental adaptation.

• Preventive maintenance - Proactive changes to reduce the likelihood of future faults (for example, refactoring or adding safeguards).

Why adaptive maintenance is correct: It specifically addresses the need to modify software so it remains compatible and functional when external environmental factors change.