The ____ Constraint Is Similar to the PRIMARY KEY Constraint

question 40

Multiple Choice

The ____ constraint is similar to the PRIMARY KEY constraint because both enforce unique values;the difference is that it allows null values in the column or columns that are named in the constraint.

• A) CHECK
• B) FOREIGN KEY
• C) UNIQUE
• D) NOT NULL

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Definitions:

Ethological Theory

A theory in psychology that emphasizes the genetic and evolutionary basis of behavior, particularly how behavior enhances survival and reproduction.

Attachment

A lasting emotional tie between two individuals.

Biologically Driven

Actions or processes influenced primarily by genetic, neurological, or physiological factors rather than environmental ones.

Survival

The ability to continue living or existing despite challenging or life-threatening conditions.