What does EHAS stand for?

• A. EDTA
• B. Heparin
• C. Any Other Additive
• D. Serum

Answer: (A)

In phlebotomy, the additive that matches the idea behind EHAS is Ethylenediaminetetraacetic acid, known as EDTA. This chemical acts as an anticoagulant by binding calcium ions, which are essential for blood clotting. By removing calcium, EDTA prevents clot formation, preserving the blood cells and allowing accurate complete blood counts and other hematology tests. That’s why this option is the best fit for what EHAS stands for in this context.

The other items don’t fit because heparin is a different anticoagulant with a distinct mechanism, used for plasma chemistry tests; serum refers to the liquid that remains after blood clots and is devoid of anticoagulants; and “any other additive” isn’t a standard label in this context.