Which coagulation disorder is associated with an increased risk of thrombosis due to a deficiency of antithrombin III?

A Protein C deficiency
B Protein S deficiency
C Antithrombin III deficiency ✓
D Factor V Leiden mutation

Explanation

Antithrombin III is a naturally occurring anticoagulant that inhibits the activity of thrombin and other coagulation factors. A deficiency of antithrombin III increases the risk of thrombosis.

Source

Williams Hematology
Hematology Hematology: Coagulation Disorders Hematology: Coagulation Disorders Hard MEDICAL Confidence: high