Which of the following statements is true about $H_3BO_3$?

Which of the following statements is $NOT$ correct for potash alum?

$H_3BO_3$ is

Consider the compounds,$BCl_3$ and $CCl_4$. How will they behave with water? Justify.

The first ionization enthalpy values (in $kJ\, mol^{-1}$) of group $13$ elements are:

Element	$B$	$Al$	$Ga$	$In$	$Tl$
Ionization Enthalpy	$801$	$577$	$579$	$558$	$589$

How would you explain this deviation from the general trend?

Given below are two statements: One is labelled as Assertion $A$ and the other is labelled as Reason $R$:
Assertion $A$ : The stability order of $+1$ oxidation state of $Ga$,$In$ and $Tl$ is $Ga < In < Tl$.
Reason $R$ : The inert pair effect stabilizes the lower oxidation state down the group.
In the light of the above statements,choose the correct answer from the options given below :