It is a field that contains a unique identifier for each record in a primary table

Select one:

a. Foreign key

b. Index

c. Primary key

d. unique

Answer: C) Primary key

Explanation:

Primary key is defined as, the set of value which uniquely identifies the row of the table. The value of the primary key are used to referred the entire record as each record has different type of values for key. And each table contain only one primary key. And the primary key cannot contain the null values.