Which category represents software that must be purchased to be legally used?

The category that represents software that must be purchased to be legally used is Licensable software. Licensable software refers to any software that is typically protected under copyright law and thus requires a formal licensing agreement for its use. This means that to legally access and utilize the software, a user or organization must acquire a license, which often involves a purchase.

Licensable software is associated with various licensing models, including proprietary licenses, which may impose limitations on redistribution and modification. The necessity of purchasing a license is critical as it respects the intellectual property rights of the software creators and ensures that they are compensated for their work.

In contrast, non-licensable software would typically refer to software that may be in the public domain or freely available for use without restrictions, which does not require a purchase. Other terms, such as Child and Driver, do not pertain to the requirement for purchasing software for legal use and are thus not relevant in this context. Understanding these distinctions is crucial in the realm of Software Asset Management, as it helps ensure compliance with legal software usage and licensing agreements.