Which one of the following represents the electronic configuration of the most electropositive element?

Red hot carbon will remove oxygen from the oxides $XO$ and $YO$ but not from $ZO$. $Y$ will remove oxygen from $XO$. Use this evidence to deduce the order of activity of the three metals $X, Y$ and $Z$ putting the most active first.

Which one of the following is the most electropositive element?

The electronic configuration of an element is $1s^2 2s^2 2p^6 3s^2 3p^3$. What is the atomic number of the element that lies immediately below this element in the periodic table?

Match List-$I$ with List-$II$.

List-$I$ (Oxide)	List-$II$ (Nature)
$A. Cl_2O_7$	$I. Amphoteric$
$B. Na_2O$	$II. Basic$
$C. Al_2O_3$	$III. Neutral$
$D. N_2O$	$IV. Acidic$

Choose the correct answer from the options given below:

Arrange the following oxides in the increasing order of their basic nature: $(a) Al_2O_3, (b) K_2O, (c) P_2O_5, (d) MgO$.