A database has three record types: 1) for supplier, a type that contains a unique supplier number, a supplier name, and a supplier address; 2) for parts, a type that contains a unique part number, a part name, a description, and a location; and 3) for purchases, a type that contains a unique supplier number referencing the supplier number in the supplier record, a part number referencing the part number in the part record, and a quantity. This database has a:
A. Relational structure.
B. Network structure.
C. Hierarchical structure.
D. Single flat file structure.