Which of the following organisms does not fix $N_2$?

Match the physiological processes given in Column-$I$ with the mineral elements given in Column-$II$:

Column-$I$	Column-$II$
$1$. Muscle contraction	$a$. $Mg^{+2}$
$2$. Digestion of food	$b$. $Ca^{+2}$
$3$. Energy exchange	$c$. $Mo$
$4$. Carbohydrate synthesis	$d$. $(PO_4)^{-3}$
$5$. Nitrogen fixation	$e$. $Cl^-$

Match the following columns:

Column-$I$	Column-$II$
$1.$ Mycorrhiza	$a.$ Free-living $N_2$-fixer
$2.$ Nostoc	$b.$ Phosphorus absorption
$3.$ Azospirillum	$c.$ Leguminous plants
$4.$ Rhizobium	$d.$ Autotrophic $N_2$-fixer

Match the following columns:

Column-$I$	Column-$II$
$(A)$ Water splitting reaction	$(1)$ Boron
$(B)$ Uptake and utilisation of $Ca^{2+}$	$(2)$ Copper
$(C)$ Synthesis of auxin	$(3)$ Chlorine
$(D)$ Redox reaction	$(4)$ Zinc

Statement $P$: In vertebrates,about $70$ percent of the total phosphorus is incorporated into bones and teeth.
Statement $Q$: Phosphorus is a structural component of vitamins like biotin and thiamine.

Which of the following plants is used as green manure in crop fields and in sandy soils?