Give the origin of Red blood cells.

The disease resulting from prolonged clotting time due to the lack of plasma thromboplastin component $(PTC)$,which is necessary for the formation of thromboplastin,is:

Biological marriage of one of the following should be avoided:

To whom can $AB$ blood group blood be donated?

Match the items given in Column $I$ with those in Column $II$ and select the correct option given below:

Column $I$	Column $II$
$(a)$ Fibrinogen	$(i)$ Osmotic balance
$(b)$ Globulin	$(ii)$ Blood clotting
$(c)$ Albumin	$(iii)$ Defence mechanism

In rabbit,the function of the spleen is