Which of the following oxides is the most acidic?

Match the following:

Oxide	Nature
$a$. $CO$	$i$. Basic
$b$. $BaO$	$ii$. Neutral
$c$. $Al_2O_3$	$iii$. Acidic
$d$. $Cl_2O_7$	$iv$. Amphoteric

Which of the following is the correct option?

Which one of the following is most basic?

The correct set that contains all kinds (basic, acidic, amphoteric, and neutral) of oxides is:

Identify the statements which are not correct?
$(i)$ $ZnO, PbO, Sb_2O_3$ are neutral oxides.
(ii) $CO$ and $NO$ are amphoteric oxides.
(iii) $CrO_3, Mn_2O_7, V_2O_5$ are basic oxides.

Among the statements $(I-IV)$,the correct ones are:
$(I)$ $Be$ has smaller atomic radius compared to $Mg$.
$(II)$ $Be$ has higher ionization enthalpy than $Al$.
$(III)$ Charge/radius ratio of $Be$ is greater than that of $Al$.
$(IV)$ Both $Be$ and $Al$ form mainly covalent compounds.