The oxygen carrier or the respiratory pigment in the blood of a frog and other vertebrates is:

Match the columns:

Column-$I$ (Blood group)	Column-$II$ (Antibody)
$A$. $A$	$P$. $b$
$B$. $B$	$Q$. $a$
$C$. $AB$	$R$. $nil$
$D$. $O$	$S$. $a$ and $b$

One of the factors required for the maturation of erythrocytes is . . . . . . .

Erythroblastosis fetalis (hemolytic disease of the newborn) is observed in marriages between:

Properties of human $RBCs$ are:
$I.$ Devoid of nucleus
$II.$ Formed in bone marrow
$III.$ Possess healing properties
$IV.$ Biconcave in shape
$V.$ Help in blood clotting
Choose the option with correct properties.

Which of the following plasma proteins is involved in the coagulation of blood?