The electronic configurations of four elements are $:-$
$(I) \ [Xe] 6s^1$
$(II) \ [Xe] 4f^{14} 5d^1 6s^2$
$(III) \ [Ar] 4s^2 4p^5$
$(IV) \ [Ar] 3d^7 4s^2$
Select the incorrect statement about these elements $:-$

Which of the following pairs shows opposite trends when moving from left to right in a period and from top to bottom in a group?

Which of the following sequences represents the atomic numbers of only representative elements?

In general,the properties that decrease and increase down a group in the periodic table respectively are

$A, B$,and $C$ are hydroxy-compounds of the elements $X, Y$,and $Z$ respectively. $X, Y$,and $Z$ are in the same period of the periodic table. $A$ gives an aqueous solution of $pH < 7$. $B$ reacts with both strong acids and strong alkalis. $C$ gives an aqueous solution which is strongly alkaline.
Which of the following statements is / are true?
$I$: The three elements are metals.
$II$: The electronegativities decrease from $X$ to $Y$ to $Z$.
$III$: The atomic radius decreases in the order $X, Y$,and $Z$.
$IV$: $X, Y$,and $Z$ could be phosphorus,aluminium,and sodium respectively.

In which of the following arrangements is the order $NOT$ according to the property indicated in the bracket?