What technology retrieves an item from a database without revealing which item is retrieved?

Private Information Retrieval (PIR) is a technology designed specifically to enable a user to retrieve data from a database without exposing which particular data item is being accessed. This is accomplished through cryptographic techniques that ensure the privacy of the query, thereby allowing the user to obtain information without revealing their search intentions to the database owner or any observing parties.

PIR is particularly important in scenarios where confidentiality is critical, such as in personal medical records or sensitive financial information. By using PIR, users can maintain their privacy while still accessing the necessary data, which is essential in today's data-driven world where information security is paramount. This technology is vital for protecting against potential misuse of query information and ensures that the user's actions remain anonymous.

In contrast, the other options relate to different aspects of data security but do not specifically address the retrieval of data while maintaining the privacy of the query itself. Data Masking is focused on obscuring data to protect sensitive information, Access Control pertains to user permissions and rights to access data, and Data Minimization emphasizes limiting data collection to only what is necessary. While all these concepts are important in the realm of data security, they do not fulfill the specific function that Private Information Retrieval is designed for.