Answer: (4) Left ventricle and Aorta
Explanation: (1)left ventricle has the thickest wall of all chambers.
(2) the left ventricle works for pumping the blood towards the heart of the tissue.
(3) and this is why more muscle are contracting inside the left ventricle that helps to produce higher force to move the blood towards the parts of the body.
(4) left ventricles pumps blood to all parts of the body.
(5) aorta has thick wall because it has to resist the pressure of the blood flow.
(6) aortic diameter is less than 3.0cm
(7) in the middle layer of aorta i.e, tunica media that have many elastic fibers and composed of smooth muscle cells.