The deficiency of which of the following causes a delay or inhibition in flowering and fruit formation in plants?

$A$: Manganese toxicity causes brown spots,chlorotic veins,and inhibition of calcium translocation to the shoot apex.
$R$: Toxic effects may be due to direct excess of micronutrients or their interference in the absorption and functioning of other nutrients.

Why is it that in certain plants deficiency symptoms appear first in younger parts of the plant,while in others they do so in mature organs?

Which mineral deficiency causes the 'Exanthema' disease in citrus plants?

Grey spots on oats are caused by the deficiency of which element?

Match the following columns:

Column-$I$	Column-$II$
$P$. Chlorosis	$I$. $Ca, Mg, Cu, K$
$Q$. Necrosis	$II$. $N, S, Mo$
$R$. Inhibition of cell division	$III$. $N, K, Mg, S, Fe, Mn, Zn, Mo$
$S$. Delay in flowering	$IV$. $N, K, S, Mo$