Which of the following keys is used to uniquely identify each record in a…

2026

Which of the following keys is used to uniquely identify each record in a table and cannot contain a NULL value?

  1. A.

    Foreign Key

  2. B.

    Candidate Key

  3. C.

    Primary Key

  4. D.

    Composite Key

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Correct answer: C

In a relational database, the Primary Key is used to uniquely identify each record in a table. It must contain unique values and cannot contain NULL values, ensuring data integrity and enabling relationships between tables.

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