The attribute of the data that has been compromised, if it is discovered that large quantities of information have been copied by the unauthorized individual, is the confidentiality. The confidentiality is the property or the characteristic of the data that ensures that the data is only accessible or disclosed to the authorized individuals or entities, and that the data is protected from the unauthorized or the malicious access or disclosure. The confidentiality of the data can be compromised when the data is copied, stolen, leaked, or exposed by an unauthorized individual or a malicious actor, such as the one who accessed the system hosting the database. The compromise of the confidentiality of the data can violate the privacy, the rights, or the interests of the data owners, subjects, or users, and can cause damage or harm to the organization’s operations, reputation, or objectives. Availability, integrity, and accountability are not the attributes of the data that have been compromised, if it is discovered that large quantities of information have been copied by the unauthorized individual, as they are related to the accessibility, the accuracy, or the responsibility of the data, not the secrecy or the protection of the data. References: CISSP All-in-One Exam Guide, Eighth Edition, Chapter 3, Security Architecture and Engineering, page 263. Official (ISC)2 CISSP CBK Reference, Fifth Edition, Chapter 3, Security Architecture and Engineering, page 279.