The primary purpose of a privacy audit framework is to confirm and demonstrate effectiveness of the privacy program in achieving objectives and regulatory compliance. Historical breaches (B) and benchmarking (D) are by-products; maximizing staff effort (C) is about audit efficiency, not program assurance.
"Privacy audits validate the effectiveness and compliance of the privacy program."

Data minimization requires collecting and using only what is necessary for the stated purpose-directly limiting privacy risk in AI development and use. Encryption (A) and masking (D) protect data post-collection, and pseudonymization (B) reduces identifiability but does not limit collection or use. Minimization addresses privacy by default at the source.
"Collect and process no more personal data than necessary for the specified purpose."

Cryptographic erasure is a data sanitization method that uses encryption to render data unreadable and unrecoverable. It is the best method when there is a need to balance the destruction of data and the ability to recycle IT assets, because it does not damage the storage media and allows it to be reused or sold. It is also faster and more environmentally friendly than physical destruction methods.
Reference:
ISACA Certified Data Privacy Solutions Engineer (CDPSE) Exam Content Outline, Domain 2: Privacy Architecture, Task 2.4: Implement data sanitization methods to ensure data privacy and security, Subtask 2.4.1: Select appropriate data sanitization methods based on the type of data and storage media.
What is Data Sanitization? | Data Erasure Methods | Imperva

Reference:
Data minimization is a privacy principle that requires limiting the collection, storage and processing of personal data to what is necessary and relevant for the intended purposes. Data minimization should be used to address data kept beyond its intended lifespan, as it helps to reduce the amount of data that is stored or retained, and to delete or dispose of data that is no longer needed or justified. Data minimization also reduces the privacy risks and costs associated with data storage and retention, such as data breaches, unauthorized access, misuse or loss of data. The other options are not effective ways to address data kept beyond its intended lifespan. Data anonymization is a technique that removes or modifies all identifiers in a data set to prevent or limit the identification of the data subjects, but it does not address the issue of data retention or deletion. Data security is a process of applying technical, administrative and physical measures to protect the confidentiality, integrity and availability of data, but it does not address the issue of data retention or deletion. Data normalization is a technique that organizes the data in a database to reduce redundancy and improve consistency, but it does not address the issue of data retention or deletion1, p. 75-76 Reference: 1: CDPSE Review Manual (Digital Version)

The best way to validate compliance with agreed-upon service levels established with a third party that processes personal data is to have a contractual right to audit, which means that the organization can conduct audits or inspections of the third party's privacy practices, policies, and procedures to verify that they meet the contractual obligations and expectations. A contractual right to audit can also help identify and address any privacy risks or gaps that may arise from the third party's processing of personal data12.
Reference:
CDPSE Exam Content Outline, Domain 1 - Privacy Governance (Governance, Management & Risk Management), Task 7: Participate in the management and evaluation of contracts, service levels and practices of vendors and other external parties3.
CDPSE Review Manual, Chapter 1 - Privacy Governance, Section 1.4 - Third-Party Management4.