Which one of the following statements is correct?

Which of the following substances is formed when $BCl_3$ reacts with water?

When orthoboric acid $(H_3BO_3)$ is subjected to strong heating,the residue left is

The correct statements from the following are:
$(A)$ Ionic radii of trivalent cations of group $13$ elements decrease down the group.
$(B)$ Electronegativity of group $13$ elements decreases down the group.
$(C)$ Among the group $13$ elements,Boron has the highest first ionisation enthalpy.
$(D)$ The trichlorides and triiodides of group $13$ elements are covalent in nature.
Choose the correct answer from the options given below:

Which of the following element$(s)$ exist in the liquid state?

Given below are two statements:
Statement $I$: Group $13$ trivalent halides get easily hydrolyzed by water due to their covalent nature.
Statement $II$: $AlCl_3$ upon hydrolysis in acidified aqueous solution forms octahedral $[Al(H_2O)_6]^{3+}$ ion.
In the light of the above statements,choose the correct answer from the options given below: