Fotis is the security administrator for a public school district. He is implementing a new student information system and is testing the code to ensure that students are not able to alter their own grades. What principle of information security is Fotis enforcing?

Integrity controls, such as the one Fotis is implementing in this example, are designed to prevent the unauthorized modification of information. There is no evidence of an attack against availability or confidentiality. Denial is an objective of attackers, rather than of security professionals, and is not relevant in this scenario that targets integrity.