What Is a Primary Key

question 10

Multiple Choice

What is a primary key?

• A)A field that uniquely identifies a given record in a table.
• B)A primary key of one table that appears as an attribute in another table and acts to provide a logical relationship between the two tables.
• C)A table that uniquely identifies a given record in a field.
• D)A foreign key of one table that appears as an entity in another table and acts to provide a logical relationship between the two records.

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Definitions:

SCN

Short for Suprachiasmatic Nucleus, a region in the brain responsible for controlling circadian rhythms.

Suprachiasmatic Nucleus

A small region in the brain located in the hypothalamus, responsible for controlling circadian rhythms.

Intergeniculate Leaflet

The intergeniculate leaflet is a small structure located between the lateral geniculate nucleus of the thalamus, involved in regulating circadian rhythms and visually related information processing.

Retinohypothalamic Tract

Neural route formed by axons of photosensitive retinal ganglion cells (pRGCs) from the retina to the suprachiasmatic nucleus; allows light to entrain the SCN’s rhythmic activity.