What term describes a property used to characterize data items of entities, such as datatype and size?

• A. Constraint
• B. Data Dictionary
• C. Attribute
• D. Block

Answer: (C)

The property used to describe data items of entities, including datatype and size, is an attribute. Attributes define the properties or characteristics that an entity has—for example, a Customer entity might have attributes like CustomerID, Name, and Email, each with its own datatype and length. In a relational schema, those attributes become columns with specified datatype and size. This differs from constraints (rules on values), a data dictionary (a repository of metadata about data), and a block (a storage unit). So, attributes are the specific labels that describe what each data item can be.