Answer:
The correct answer is Option A (Referential integrity)
Step-by-step explanation:
When a relational database table is in first normal form, that means it has no repeating fields or groups of fields, and hence all rows have the same columns, while if a relational database table is in second normal form, it implies that every non-key field is functionally dependent on the primary key. If can be in the third normal form if no non-key field is functionally dependent on any other non-key field.
A relational database on its own is a universal approved database model whose data is stored in tables divided into records and fields that serve as an information unit that organizes data points for easy access.
In the relational database, foreign keys are being checked to reference the primary key and enforce referential integrity so as to ensure that the foreign key must have a matching primary key. It means the reference from a row in one table to another table must be valid. Referential integrity concerns the concept of a foreign key normally enforced by the database management system.