Match the following columns:

Column $- I$	Column $- II$
$a$. Bicuspid valve	$p$. Brain
$b$. Nephron	$q$. Liver
$c$. Alveoli	$r$. Heart
$d$. Cerebrum	$s$. Kidney
	$t$. Lungs

$A$: In an open circulatory system,the volume of blood is high,but blood pressure is low and irregular.
$R$: In a closed circulatory system,the volume of blood is limited,and blood pressure is high and regular.

Match the following:
Disease: Cause
$A.$ Diabetes: $6.$ Increase in blood sugar level
$B.$ Uraemia: $7.$ Urea is in excess in blood
$C.$ Anaemia: $5.$ Fall in $RBC$ count
$D.$ Polycythemia: $3.$ Rise in $RBC$ count
$E.$ Pernicious or Megaloblastic anaemia: $2.$ Deficiency of vitamin ${B_{12}}$
$F.$ Leukemia: $8.$ Pathological increase in $WBC$
$G.$ Thrombocytopenia: $9.$ Decrease in the number of platelets
$H.$ Leucopenia: $4.$ Fall of $WBC$ count
$I.$ Leucocytosis: $1.$ Rise in $WBC$ count
The correct matching sequence is:

Oedema is defined as:

Cords of Billroth are blood-filled spaces found in which of the following organs?

Consider the following four statements regarding the human circulatory system:
$(a)$ Arteries have thick walls and a narrower lumen compared to veins.
$(b)$ Angina is a sudden chest pain.
$(c)$ In the $ABO$ blood grouping system,a person with blood group $AB$ can donate blood to anyone.
$(d)$ Calcium ions play a significant role in blood clotting.
Which two of the above statements are correct?