Which of the following is true for an element in group $13$ of the periodic table?

The correct statements from the following are:
$(A)$ The decreasing order of atomic radii of group $13$ elements is $Tl > In > Ga > Al > B$.
$(B)$ Down the group $13$ electronegativity decreases from top to bottom.
$(C)$ $Al$ dissolves in dil. $HCl$ and liberates $H_2$,but conc. $HNO_3$ renders $Al$ passive by forming a protective oxide layer on the surface.
$(D)$ All elements of group $13$ exhibit a highly stable $+1$ oxidation state.
$(E)$ Hybridisation of $Al$ in $[Al(H_2O)_6]^{3+}$ ion is $sp^3d^2$.
Choose the correct answer from the options given below:

What are electron-deficient compounds? Are $BCl_3$ and $SiCl_4$ electron-deficient species?

Diborane reacts with ammonia under different conditions to give a variety of products. Which one among the following is not formed in these reactions?

Select the correct statements from the following:
$A$) Aluminium liberates $H_2$ gas with dil. $HCl$ but not with aqueous $NaOH$.
$B$) Formula of sodium metaborate is $Na_3BO_3$.
$C$) Boric acid is a weak monobasic acid.
$D$) For thallium,$+1$ state is more stable than $+3$ state.

Anhydrous $AlCl_3$ cannot be obtained from which of the following reactions?