**Core Concept**
Warfarin is an oral anticoagulant that inhibits the synthesis of vitamin K-dependent clotting factors in the liver. Urgent reversal of warfarin therapy is necessary in life-threatening situations such as severe bleeding or prior to emergency surgery. The goal is to rapidly restore normal coagulation function.

**Why the Correct Answer is Right**
Fresh frozen plasma (FFP) contains all the clotting factors, including vitamin K-dependent factors, and can rapidly correct the coagulopathy caused by warfarin. FFP is administered intravenously and can reverse warfarin's anticoagulant effect within minutes. This makes it an ideal choice for urgent reversal of warfarin therapy.

**Why Each Wrong Option is Incorrect**
**Option A:** Vitamin K is used to reverse warfarin, but it takes time to take effect (around 6-24 hours). It is not the best choice for urgent reversal.
**Option B:** Prothrombin complex concentrate (PCC) can also reverse warfarin, but it is not as readily available as FFP and may have a higher risk of thrombosis.
**Option C:** Platelet transfusions are not effective in reversing warfarin's anticoagulant effect, as the problem lies with the clotting factors, not platelets.
**Option D:** Desmopressin can be used to correct bleeding in patients with hemophilia A or von Willebrand disease, but it is not effective in reversing warfarin's anticoagulant effect.

**Clinical Pearl / High-Yield Fact**
FFP should be used in combination with vitamin K for warfarin reversal, as it can rapidly correct the coagulopathy and provide a more sustained effect.

**Correct Answer: C. Prothrombin complex concentrate (PCC) can also reverse warfarin, but it is not as readily available as FFP and may have a higher risk of thrombosis.