What is the main purpose of the Orange Book?

The primary aim of the Orange Book, formally known as the "Trusted Computer System Evaluation Criteria" (TCSEC), is to establish a methodology for evaluating the security of computer systems. This framework is designed to assess the capability of systems to withstand various threats and manage sensitive information appropriately. The evaluation process defined by the Orange Book supports organizations in understanding the security features of systems, ensuring they meet specific standards before they are deployed in environments that require high levels of confidentiality and integrity.

This makes option B the correct choice, as it encapsulates the essence of the Orange Book, which focuses on the assessment and evaluation of security measures in computer systems.

The other choices, while related to security, do not directly align with the primary function of the Orange Book. Developing secure operating environments, outlining secure programming practices, and classifying computers based on security levels are important aspects of overall information security but are not the central focus of the Orange Book’s evaluation criteria. Instead, these may be components or recommendations within the broader context of creating secure systems, but they do not define the key purpose of the Orange Book itself.