Final answer:
The noble gases are the least reactive nonmetals.
Step-by-step explanation:
The family containing the least reactive nonmetals is the noble gases. The noble gases, also known as Group 18 elements, include helium, neon, argon, krypton, xenon, and radon. These elements have a full valence electron shell, making them very stable and unreactive. They rarely form compounds with other elements and are typically found in their elemental forms in nature.
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