Nitrates of soil are also leached deep into the earth by . . . . . . .

Assertion : Plants absorb sulphur in the form of sulphate ions.
Reason : Sulphur bacteria are required for the formation of sulphate.

Match Column-$I$ and Column-$II$ and choose the correct option given below the columns.

Column-$I$ (Element)	Column-$II$ (Function)
$A$. Calcium	$I$. Required for ionic balance
$B$. Boron	$II$. Essential for constitution of nucleic acid
$C$. Phosphorus	$III$. Required for absorption of calcium
$D$. Chlorine	$IV$. Required to activate respiratory enzyme
$E$. Manganese	$V$. Required for synthesis of mitotic spindle

Given below are two statements:
Statement $I$: Diazotrophs are the nitrogen-fixing microorganisms,which are exclusively symbiotic.
Statement $II$: Organic fertilizers include farmyard manure,compost,and green manure.
In light of the above statements,choose the most appropriate answer from the options given below.

Assertion $A$: Leguminous plants increase soil fertility.
Reason $R$: Azotobacter fixes atmospheric $N_2$.

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