What is the primary mechanism by which antithrombin III inhibits coagulation?

A By binding to and activating thrombin
B By binding to and inhibiting thrombin and other coagulation factors ✓
C By promoting the formation of fibrin clots
D By inhibiting the release of tissue factor

Explanation

Antithrombin III is a serine protease inhibitor that binds to and inhibits thrombin and other coagulation factors, thereby preventing excessive coagulation.

Source

Guyton and Hall Textbook of Medical Physiology
Hematology Hematology: Coagulation Disorders Hematology: Coagulation Disorders Medium MEDICAL Confidence: high