What is the Unstructured Data Storage Function (UDSF)?

What is the Unstructured Data Storage Function (UDSF)?
A . This network function exposes 5G Core Network functionalities available to 3rd parties, so that 3rdparty capabilities and events may be securely exposed by the Network Exposure Function (NEF).
B . This network function is part of data repositories in the Common Data Layer. It stores 3GPP standardized data.
C . This network function is part of data repositories in the Common Data Layer and in opposition to the UDR, it stores non-standardized C Unstructured C data.
D . This network function stores or retrieves subscriptions, profiles, and authentication data to or from the data repositories. It offers services to the AMF, SMF, NEF and AUSF using the Service Based Interface.

Answer: A

Reference: https://webthesis.biblio.polito.it/12557/1/tesi.pdf