Phosphorus is required for making
$I.$ shell
$II.$ bones
$III.$ teeth
Choose the correct option

$A$ farmer adds/supplies $Na, Ca, Mg$ and $Fe$ regularly to his field and yet he observes that the plants show deficiency of $Ca, Mg$ and $Fe$. Give a valid reason and suggest a way to help the farmer improve the growth of plants.

Select the correct match for $X$ and $Y$.

Column $X$	Column $Y$
$(1)$ Muscle contraction	$(P)$ $Mg^{+2}$
$(2)$ Digestion of food	$(Q)$ $Ca^{+2}$
$(3)$ Energy exchange	$(R)$ $Mo$
$(4)$ Carbohydrate synthesis	$(S)$ $PO_4^{-3}$
$(5)$ Nitrogen fixation	$(T)$ $Cl^{-}$

Select the incorrect statement from the following options.

Identify the correct pair:

Column-$I$	Column-$II$
$P$. Phosphorus	$I$. Splitting of water to liberate oxygen during photosynthesis
$Q$. Potassium	$II$. Constituent of cell membranes and all nucleotides
$R$. Magnesium	$III$. In more abundant quantities in the meristematic tissue,buds,leaves,and root tips
$S$. Manganese	$IV$. Constituent of the ring structure of chlorophyll and helps to maintain the ribosome structure

$P - Q - R - S$

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.