Strong encryption methods are the BEST control to protect customer personal information that is stored in the cloud, because they help to prevent unauthorized access, disclosure, modification, or deletion of the data by encrypting it at rest and in transit. Encryption is the process of transforming data into an unreadable format using a secret key or algorithm, so that only authorized parties can decrypt and access the data. Encryption can help to protect the confidentiality, integrity, and availability of the data, as well as to comply with legal and regulatory requirements.
References =
CISM Review Manual, 16th Edition, ISACA, 2020, p. 72: "Encryption is the process of transforming data into an unreadable format using a secret key or algorithm." CISM Review Manual, 16th Edition, ISACA, 2020, p. 73: "Encryption can help to protect the confidentiality, integrity, and availability of data, as well as to comply with legal and regulatory requirements for data protection." Saas Data Security: Protecting Your Customers' Information In The Cloud - Fresent's Blog: "Encryption and Data Protection: One of the most effective ways to protect sensitive data in the cloud is to encrypt it both at rest and in transit. Encryption is the process of transforming data into an unreadable format using a secret key or algorithm, so that only authorized parties can decrypt and access the data."

Reputational damage is often intangible, subjective, and hard to quantify, making it the most challenging aspect to measure.
"Reputation impact is difficult to quantify and may have long-term effects that are not immediately apparent."
- CISM Review Manual 15th Edition, Chapter 4: Incident Management, Section: Post-incident Analysis* ISACA practice questions highlight that reputational damage is uniquely challenging to measure accurately.

According to the CISM Review Manual, the primary objective when establishing a new information security program is to execute the security strategy that has been defined and approved by the senior management. The security strategy provides the direction, scope, and goals for the information security program, and aligns with the business objectives and requirements. Minimizing organizational risk, optimizing resources, and facilitating operational security are possible outcomes or benefits of the information security program, but they are not the primary objective.
References = CISM Review Manual, 27th Edition, Chapter 3, Section 3.1.1, page 1151.

Documenting information security responsibilities within job descriptions is the most effective way to convey information security responsibilities across an organization because it clearly defines the roles, expectations, and accountabilities of each employee regarding information security. It also helps to align the information security objectives with the business goals and performance indicators, and to ensure compliance with the security policies and standards.
References = CISM Review Manual 15th Edition, What is CISM? - Digital Guardian