The most important thing for an IS auditor to examine when reviewing an organization's privacy policy is its legitimate purpose for collecting personal data. A legitimate purpose is a clear and specific reason for collecting personal data that is necessary for the organization's business operations or legal obligations, and that respects the rights and interests of the data subjects. A legitimate purpose is the basis for establishing a lawful and fair processing of personal data, and it should be communicated to the data subjects in the privacy policy. The other options are not as important as the legitimate purpose in reviewing the privacy policy.
Explicit permission from regulators to collect personal data is not always required, as there may be other lawful bases for data collection, such as consent, contract, or public interest. Sharing of personal information with third-party service providers is not prohibited, as long as there are adequate safeguards and agreements in place to protect the data. The encryption mechanism selected by the organization for protecting personal data is a technical control that can enhance data security, but it does not determine the legality or fairness of data collection. References: CISA Review Manual (Digital Version), Chapter 5, Section 5.3.2