Which of the following does not depend on stable electronic configuration?

$X$,$Y$,and $Z$ are elements of the same period and belong to the $p$-block. $Y$ has a positive value of $\Delta_{eg}H$ (electron gain enthalpy),and $Z$ has the highest $2^{nd}$ ionization energy $(I.E.)$ among them. What is the correct order of their atomic numbers?
$(a)$ $X < Y < Z$
$(b)$ $X < Z < Y$
$(c)$ $Y < Z < X$
$(d)$ $Z < Y < X$

Which of the following statement$(s)$ is/are correct?

Observe the following statements:
$I$. The physical and chemical properties of elements are periodic functions of their electronic configuration.
$II$. Electronegativity of fluorine is less than the electronegativity of chlorine.
$III$. Electropositive nature decreases from top to bottom in a group.
The correct answer is:

Identify the correct statements from the following.
$(i)$ In the periodic table,about $78 \%$ of elements are metals.
$(ii)$ In a group,the metallic character decreases from top to bottom and in a period the nonmetallic character decreases from left to right.
$(iii)$ The element $Ho$ belongs to $f-$block.

Which of the following statements is incorrect?