Which of the Following Is a Specialization Hierarchy Overlapping Constraint

question 32

Multiple Choice

Which of the following is a specialization hierarchy overlapping constraint scenario in case of partial completeness?

• A) Subtype sets are unique.
• B) Supertype has optional subtypes.
• C) Subtype discriminators cannot be null.
• D) Subtype does not have a supertype.

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Definitions:

Vanadium

A chemical element with symbol V and atomic number 23, known for its strong structural metals and use as a catalyst.

Technetium

A chemical element with symbol Tc and atomic number 43, notable for being the lightest element whose isotopes are all radioactive.

Noble Gases

A group of chemical elements with similar properties under standard conditions, including being odorless, colorless, monatomic gases with very low chemical reactivity.

Inert Gases

A group of gases which are non-reactive under a set of given conditions, including helium, neon, argon, krypton, xenon, and radon.