The element that does $NOT$ show catenation is

Given below are two statements:
Statement $I$ : $SiO_2$ and $GeO_2$ are acidic while $SnO$ and $PbO$ are amphoteric in nature.
Statement $II$ : Allotropic forms of carbon are due to property of catenation and $p \pi-d \pi$ bond formation.
In the light of the above statements,choose the most appropriate answer from the options given below:

The basic building unit of all silicates is

$(BN)_n$ exists in

Consider the following statements:
Statement-$I$: $CCl_4$ does not undergo hydrolysis,but $SiCl_4$ undergoes hydrolysis.
Statement-$II$: Thermal and chemical stability of $GeX_4$ is more than $GeX_2$.
The correct answer is:

What is the increasing order of stability of the $+2$ oxidation state for the given group $14$ elements?