Which of the Following Is True About a Key

question 57

Multiple Choice

Which of the following is true about a key?

• A) It may be unique.
• B) It may be non-unique.
• C) In may identify more than one row.
• D) Both A and B
• E) All of the above

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Definitions:

Immune System

The immune system is the body's defense mechanism against pathogens, consisting of a network of cells, tissues, and organs that work together to protect the body from disease.

Extracellular Antigens

Foreign substances outside cells that stimulate an immune response.

Subpopulation

A distinct group within a larger population that can be identified by certain characteristics or behaviors.

T Cells

A type of white blood cell that is vital for the immune response, recognizing and responding to pathogens and infected cells.