The deficiency of calcium is observed in the absence of vitamin ...............

Match the mineral deficiency disorders given in Column $I$ with their symptoms given in Column $II$.

Column $I$ (Disorder)	Column $II$ (Description)
$i$. Chlorosis	$a$. Localised death of tissues in leaves
$ii$. Necrosis	$b$. Premature fall of flowers,fruits and leaves
$iii$. Mottling	$c$. Yellowing of leaves due to absence of chlorophyll
$iv$. Abscission	$d$. Appearance of green and non-green patches on leaves

Choose the correct option from below.

What type of disease is Rickets?

How are the terms 'critical concentration' and 'deficient' different from each other in terms of the concentration of an essential element in plants? Can you find the values of 'critical concentration' and 'deficient' for minerals $Fe$ and $Zn$?

Plants grow in a magnesium-deficient soil,but what happens if urea is added to the soil?

Yellowish edges appear in leaves deficient in $....$