The technique that an organization should use to assure application integrity is digital signing. Digital signing is a technique that uses cryptography to generate a digital signature for a message or a document, such as an application. The digital signature is a value that is derived from the message and the sender’s private key, and it can be verified by the receiver using the sender’s public key. Digital signing can help to assure application integrity, which means that the application has not been altered or tampered with during the transmission or storage. Digital signing can also help to assure application authenticity, which means that the application originates from the legitimate source. Application authentication, input validation, and device encryption are not techniques that can assure application integrity, but they can help to assure application security, usability, or confidentiality, respectively. References: CISSP All-in-One Exam Guide, Eighth Edition, Chapter 5: Security Engineering, page 607; Official (ISC)2 Guide to the CISSP CBK, Fifth Edition, Chapter 3: Security Architecture and Engineering, page 388.