Which of the following is least likely to behave as a Lewis base?

Observe the following sets:

Label	Order	Property
$i.$	$NH_3 > H_2O > SO_2$	Bond angle
$ii.$	$H_2O > NH_3 > H_2S$	Dipole moment
$iii.$	$N_2 > O_2 > H_2$	Bond enthalpy
$iv.$	$NO^{+} > O_2 > O_2^{2-}$	Bond order

Which of the above sets are correctly matched?

Which of the following molecules has an axis of symmetry and a coaxial plane of symmetry?

Solid $BeH_2$ and solid $BeCl_2$ differ in

Which one of the following molecules contains no $\pi$ bond?

The option$(s)$ in which at least three molecules follow the Octet Rule is(are):
$(A)$ $CO_2, C_2H_4, NO$ and $HCl$
$(B)$ $NO_2, O_3, HCl$ and $H_2SO_4$
$(C)$ $BCl_3, NO, NO_2$ and $H_2SO_4$
$(D)$ $CO_2, BCl_3, O_3$ and $C_2H_4$