The correct answer is (a) Atherosclerosis
Easy explanation: Sclerosis stands for hardening. The deposition of the plaque in blood vessels is called as Atherosclerosis. Multiple Sclerosis is a problem occurring in the nerves of the spinal chord. The arterial blood vessel has three layers. Tunica Intima is the innermost layer, the layer blood is in contact with while Tunica Media is the central layer, providing support and acting as a shock absorber.