According to the CRISC Review Manual, formal approval of the account by the user's manager is the best evidence that a user account has been properly authorized, because it ensures that the user's role and access rights are consistent with the business needs and the principle of least privilege. The user's manager is responsible for verifying the user's identity, job function, and access requirements, and for approving or rejecting the account request. The other options are not the best evidence of proper authorization, because they do not involve the user's manager's approval. An email from the user accepting the account is a confirmation of the account creation, but it does not indicate that the account was authorized by the user's manager. Notification from human resources that the account is active is an administrative process that does not verify the user's access rights and role. User privileges matching the request form is a verification of the account configuration, but it does not ensure that the request form was approved by the user's manager. References = CRISC Review Manual, 7th Edition, Chapter 4, Section 4.1.2, page 163.