Answer:
The correct option is A) Tunica media and, therefore, the ability of blood cells to change their diameter
Explanation:
Tunica media can be described as the layer which is present in the middle of arteries and veins. This middle layer lies between the tunica indica, which is present inside, and tunica externa, which is present outside.
The tunica media is made up of smooth muscle cells and elastic tissues. The tunica media hence provides thickness to the blood vessels. If the smooth vessels are destroyed, the tunica media will be affected and there will be little rise in the diameter of these blood vessels.
