A network security specialist is tasked to implement a security measure that monitors the status of critical files in the data center and sends an immediate alert if any file is modified. Which aspect of secure communications is addressed by this security measure?

Secure communications consists of four elements: Data confidentiality – guarantees that only authorized users can read the message
Data integrity – guarantees that the message was not altered
Origin authentication – guarantees that the message is not a forgery and does actually come from whom it states
Data nonrepudiation – guarantees that the sender cannot repudiate, or refute, the validity of a message sent