Which statement best describes LDL's role in plaque formation?

• A. HDL cholesterol deposits on artery walls forming plaque
• B. Cholesterol dissolves plaque
• C. Blood flows faster with more cholesterol
• D. LDL cholesterol deposits on artery walls forming plaque

Answer: (D)

LDL's role in plaque formation centers on transporting cholesterol that can accumulate in artery walls. LDL particles circulate in the blood and, when they infiltrate a damaged arterial endothelium, cholesterol builds up in the inner wall (the intima). Oxidized LDL attracts immune cells, and macrophages ingest this cholesterol, becoming foam cells. The buildup of foam cells and surrounding cells leads to a fatty streak that develops into a fibrous plaque, narrowing the artery and potentially rupturing to trigger a clot. In contrast, HDL helps remove cholesterol from plaques and transport it to the liver for disposal, which is why HDL is protective. The other statements aren’t accurate: HDL doesn’t deposit plaque; cholesterol doesn’t dissolve plaque; and more cholesterol doesn’t make blood flow faster—the plaque typically reduces blood flow.