Consider the following reaction,

$\mathrm{Al}+\mathrm{NaOH}\to \mathrm{X}+{\mathrm{H}}_2$
${\mathrm{B}}_2{\mathrm{H}}_6<mspace\; width="1em"></mspace>+<mspace\; width="1em"></mspace>{\mathrm{NH}}_3\to \mathrm{Y}$

X and Y in the above reaction are:

$1.<mspace\; width="1em"></mspace>\mathrm{X}=<mspace\; width="1em"></mspace>\mathrm{Al}{\left(\mathrm{OH}\right)}_2<mspace\; width="1em"></mspace>;<mspace\; width="1em"></mspace>\mathrm{Y}<mspace\; width="1em"></mspace>=<mspace\; width="1em"></mspace>{\mathrm{N}}_2\left[{\mathrm{BH}}_4\right]$
$2.<mspace\; width="1em"></mspace>\mathrm{X}<mspace\; width="1em"></mspace>=\mathrm{Na}\left[\mathrm{Al}{\left(\mathrm{OH}\right)}_4\right]<mspace\; width="1em"></mspace>;<mspace\; width="1em"></mspace>\mathrm{Y}<mspace\; width="1em"></mspace>={\mathrm{N}}_3{\mathrm{B}}_3{\mathrm{H}}_6$
$3.<mspace\; width="1em"></mspace>\mathrm{X}=<mspace\; width="1em"></mspace>\mathrm{Na}\left[\mathrm{Al}{\left(\mathrm{OH}\right)}_4\right]<mspace\; width="1em"></mspace>;<mspace\; width="1em"></mspace>\mathrm{Y}<mspace\; width="1em"></mspace>=<mspace\; width="1em"></mspace>{\mathrm{B}}_3{\mathrm{N}}_2$
$4.<mspace\; width="1em"></mspace>\mathrm{None}<mspace\; width="1em"></mspace>\mathrm{of}<mspace\; width="1em"></mspace>\mathrm{the}<mspace\; width="1em"></mspace>\mathrm{above}$

A compound among the following that is least likely to behave as a Lewis base is:

The correct statement(s) regarding thallium is/are :

1. Thallium displays both +1, and +3 oxidation states.

2. It resembles group 1 metals in some reactions.

3. Thallium only shows a +1 oxidation state.

4. Both (1) and (2)