**Question:** In malignant hypertension, seen is - a) Hyalinised arterioles, b) Replacement by necrotizing arteriolitis, c) Calcification, d) Atherosclerosis

**Core Concept:** Malignant hypertension refers to a severe and rapidly progressive form of high blood pressure (BP), characterized by damage to small blood vessels and organs. The correct answer to this question involves understanding the pathological changes that occur in malignant hypertension.

**Why the Correct Answer is Right:** In malignant hypertension, the primary pathological change occurs in small arterioles, where they undergo hyalinisation, which is the accumulation of hyaline (a proteinaceous substance) in the vessel walls. This causes narrowing of the arterioles and results in elevated blood pressure. Additionally, replacement by necrotizing arteriolitis (inflammation and destruction of arterioles) can also occur, leading to further vascular damage.

**Why Each Wrong Option is Incorrect:**

a) Hyalinised arterioles: Correct - this is a primary feature of malignant hypertension, leading to increased resistance and elevated blood pressure.

b) Replacement by necrotizing arteriolitis: Correct - this is another feature of malignant hypertension, causing further damage to the arterioles.

c) Calcification: This is a feature of atherosclerosis, not malignant hypertension. Calcification occurs in the arterial walls due to atherosclerotic plaque formation, which is a different condition than malignant hypertension.

d) Atherosclerosis: Atherosclerosis involves the accumulation of fatty plaques in the arterial walls, particularly in larger arteries. This is a different condition than malignant hypertension, which primarily involves small arterioles.

**Correct Answer:** In malignant hypertension, the primary features are hyalinisation and replacement by necrotizing arteriolitis. These changes result in narrowing of small arterioles, leading to increased vascular resistance and elevated blood pressure. The other options (calcification and atherosclerosis) are features of different pathological conditions and are incorrect in this context.