The correct answer is: D. All of the above
A scheme describes data elements, records and files, and record relationships.
A data element is the smallest unit of data that has meaning in a database. It is a single piece of information, such as a name, address, or phone number.
A record is a collection of data elements that describes a single entity, such as a customer or an employee.
A file is a collection of records that are related to each other in some way. For example, a file might contain all of the records for customers who have ordered products from a company.
Record relationships are the ways in which records are related to each other. For example, a customer record might be related to an order record by the customer’s ID number.
A scheme is a blueprint for a database. It defines the data elements, records, files, and record relationships that will be used in the database.