Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A : In TlI₃, isomorphous to CsI₃, the metal is present in +1 oxidation state.

Reason R : Tl metal has fourteen f electrons in the electronic configuration.

In the light of the above statements, choose the most appropriate answer from the options given below:

HClO₄ is the most acidic compound.

Group number = 11 (Atomic number = 111)

Heavier element of p block do not from pπ− pπ bonds as their atomic orbital are so large and diffius that they cannot have effecitve overlapping.

The inertness of ? subshell electrons towards bond formation is known as inert pair effect. This effect increases down the group thus, for Sn,  oxidation state is more stable, whereas, for Pb,  oxidation state is more stable, i.e.,  is reducing while  is oxidising.