Final answer:
b) Heparin is the anticoagulant administered via IV or SQ for immediate anticoagulation, often in surgical settings to prevent clot formation.
Step-by-step explanation:
The anticoagulant that is given for immediate anticoagulation by IV (intravenous) or SQ (subcutaneous) route is heparin. Heparin is a fast-acting anticoagulant that is used therapeutically in situations such as surgical procedures to prevent the formation of blood clots. It acts by inactivating certain factors in the coagulation pathway, including factor X, and opposes the conversion of prothrombin (factor II) into thrombin. Other anticoagulants like warfarin (Coumadin), enoxaparin, rivaroxaban (Xarelto), dabigatran (Pradaxa), and apixaban (Eliquis) are also used for preventing and treating thrombosis, but heparin is the drug of choice for immediate action.