Look at the following tables and then choose the correct statement:
ARTISTS
Airtist_id Airtist_Name
-----------------------------------
1 Bono
2 Cher
ALBUM
artist_id Album_name
------------------------------------
3 Eat the rich
a. The above picture is an example of a database that has not enforced referential integrity
b. The above picture is an example of a database that has not enforced entity integrity
c. The above picture is an example of a database that has not enforced domain integrity
d. All of the others
Answer: B