Of the following,the ion with the smallest ionic radius is

The radii of $F, F^{-}, O$ and $O^{2-}$ are in the order of :-

What happens to the atomic radius of $p$-block elements as we move from left to right across a period in the periodic table?

The size of the isoelectronic species $Cl^{-}$,$Ar$,and $Ca^{2+}$ is affected by

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$:
Assertion $A$: The ionic radii of $O^{2-}$ and $Mg^{2+}$ are same.
Reason $R$: Both $O^{2-}$ and $Mg^{2+}$ are isoelectronic species.
In the light of the above statements,choose the correct answer from the options given below:

The increasing order of the atomic radii of the following elements is
$a. C, b. O, c. F, d. Cl, e. Br$