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Generally all inert gases like , He,Ne,A...

Generally all inert gases like , He,Ne,Ar,Kr,Xe are available as monoatomic elements.
Guess the reason.

A

They are more reactive

B

Their valency is zero

C

Their valency is less than 8

D

They are unstable

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VGS PUBLICATION-BRILLIANT-ATOMS ,MOLECULES AND CHEMICAL REACTIONS-EXERCISE
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