Which blood component plays a crucial role in the regulation of blood coagulation by binding to and inhibiting factor Xa?

A Antithrombin III ✓
B Protein C
C Protein S
D Tissue factor pathway inhibitor

Explanation

Antithrombin III is a serine protease inhibitor that binds to and inhibits factor Xa, preventing excessive coagulation.

Source

Hematology: Clinical Principles and Applications
Hematology Hematology: Blood Components Hematology: Blood Components Hard MEDICAL Confidence: high