In general one or more attributes will contibute to the primary - but not necessarily all of them.
This is true for a relation in BCNF. A relation in 3rd normal form might not have this property.
A relation in 3rd normal form may also be in 4th normal form. However there are exceptional cases where a relation is in third normal form but NOT in 4th normal form.
A given relation is known to be in third normal form. Select the statement which can be inferred from this:
All attributes contribute to the primary key
Each non-key attribute determines the primary key
Each non-key attribute is determined by the primary key
Every determinant is a candidate key
The relation is not in fourth normal form.
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