Identify the incorrect statement from the following:

Carbon has the ability to form $\displaystyle \mathrm{p} \pi-\mathrm{p} \pi$ multiple bond with itself.

$\displaystyle \mathrm{ECl}_3(\mathrm{E}=\mathrm{B}$ and $\displaystyle \mathrm{Al})$ is a monomer when $\displaystyle \mathrm{E}=\mathrm{B}$ and a dimer when $\displaystyle \mathrm{E}=\mathrm{Al}$.

The order of catenation property of Group $\displaystyle 14$ elements is $\displaystyle \mathrm{C} \gg \mathrm{Si}>\mathrm{Ge} \approx \mathrm{Sn}$.

Oxygen exhibits only $\displaystyle -2$ oxidation state.