Final answer:
The term described in the question is a 'foreign key', which is a field in one table that matches the primary key in another table. The correct answer is D. none of the above, as 'foreign key' is not listed among the options.
Step-by-step explanation:
A foreign key is a field (or collection of fields) in a table whose value is required to match the value of the primary key for a second table. In the options provided:
- A. secondary key
- B. field key
- C. backup primary key
- D. none of the above
The correct answer is D. none of the above, because the term 'foreign key' was not listed but that is what is described in the question. A foreign key creates a relationship between two tables and enforces referential integrity, ensuring that the value in the foreign key field matches a value in the primary key of another table. This is distinct from a 'primary key', which uniquely identifies each record in a table, or a 'secondary key', which is an alternative key used for indexing and retrieval purposes.