When customizing out-of-the-box (OOTB) artifacts in RSA, which customization is compliant?
A. Modifying relationships in place between OOTB classes.
B. Assigning OOTB structs to other OOTB structs.
C. Creating a new foreign key where the OOTB Entity is the child.
D. Assigning a custom struct to an OOTB struct or entity.