The process of changing software to enhance its functionality is known as

Perfective maintenance is the process of modifying software to improve or enhance functionality, performance, usability, maintainability, or other desirable characteristics after release. In software quality engineering, maintenance is classified by purpose. Corrective maintenance fixes defects discovered after delivery. Adaptive maintenance changes the software so it can operate in a changed environment, such as a new operating system, database, regulation, or interface. Preventive maintenance changes software to reduce future risk, improve maintainability, or prevent potential failures. The question specifically states that the software is being changed to enhance functionality, which matches perfective maintenance. This type of maintenance often results from user feedback, business improvement needs, or requests for additional capabilities.

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