The octet rule was given by Lewis. It states that elements tend to bond in such a way that each atom has eight electrons in its valence shell, giving it the same electronic configuration as a noble gas.

Among the given options ${\mathrm{SF}}_6(12 \mathrm{e}), {\mathrm{PCl}}_5\left(10\mathrm{e}\right), {\mathrm{XeF}}_2(10 \mathrm{e})$ does not follow octet rule. As we can see that in none of them, the central atom has 8 electrons in its valence shell. They are also called expended octet.