Which of the following is not formed during the hydrolysis (partial / full) of ${\mathrm{XeF}}_6$?

The correct statements from below are:

(I) ${\mathrm{H}}_3{\mathrm{BO}}_3$ is a liquid
(II) ${\mathrm{H}}_3{\mathrm{BO}}_3$ forms a layer structure
(III) In ${\mathrm{H}}_3{\mathrm{BO}}_3,$ each ${\mathrm{BO}}_3$ unit is joined by hydrogen bonds
(IV) ${\mathrm{H}}_3{\mathrm{BO}}_3$ is tribasic.