Mary is responsible for database management and security. She is trying to remove redundancy in the database. What is this process called?

Normalization is the process of removing duplicate or redundant data from a database. There are typically four levels of normalization ranging from 1N at the lowest (i.e., the most duplication) to 4N at the highest (i.e., the least duplication).
Although database integrity is important, that is not what is described in the question.
Integrity checking usually refers to checking the integrity of files.
Deprovisioning is a virtualization term for removing a virtual system (server, workstation, etc.) and reclaiming those resources, and in the context of identity management means removing an account or permissions.
Baselining involves setting security standards.