The molecule having an atomicity of 4 is :

Atomicity: The number of atoms constituting a molecule is known as its atomicity.


Sulphur molecule (S8) : Atomicity is 8


Ozone molecule (O3): Atomicity is 3


Phosphorus molecule (P4): Atomicity is 4


Methane molecule (CH4): Atomicity is 5


Thus, option C is correct.

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