The blood pressure is high in

Which vessel supplies blood to the heart muscle?

Which of the following is another characteristic of the circulatory system in animals where the volume of blood is limited?

Which one of the following has an elastic wall?

Match the following columns:

Column-$I$	Column-$II$
$P$. Tunica intima	$I$. Smooth muscle
$Q$. Tunica media	$II$. Squamous epithelium
$R$. Tunica externa	$III$. Fibrous connective tissue

Assertion : When there is a fall in the blood pressure due to loss of blood volume,this is compensated by vasoconstriction of veins.
Reason : Veins hold the extra amount of blood which can be shifted to the arteries as required.