For a service provider, which of the following MOST effectively addresses confidentiality concerns for customers...

 For a service provider, data segregation is the most effective way to address confidentiality concerns for customers using cloud computing. Data segregation is the process of separating the data of different customers or tenants in a shared cloud environment, so that they cannot access or interfere with each other’s data. Data segregation can be achieved by using encryption, access control, virtualization, or other techniques. Data segregation can help to protect the confidentiality, integrity, and availability of the customer’s data, as well as to comply with the privacy and regulatory requirements. Hash functions, file system permissions, and non-repudiation controls are not the most effective ways to address confidentiality concerns for customers using cloud computing, as they do not provide the same level of isolation and protection as data segregation. References: CISSP All-in-One Exam Guide, Eighth Edition, Chapter 3, Security Architecture and Engineering, page 337. Official (ISC)2 CISSP CBK Reference, Fifth Edition, Chapter 3, Security Architecture and Engineering, page 353.