This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Pharmacology
All are true about warfarin except 
Select and explain. 
A. It inhibits the activation of vitamin K dependent clotting factors, B. It's half life is 36hrs, C. It can cross placenta, D. It's dose is increased in liver disease
D: It's dose is increased in liver disease
Answer: D: It's dose is increased in liver disease 
Explanation: Refer Katzung 11/e p595 Warfarin is an oral anticoagulant that acts by inhibiting the gamma carboxylation of glutamate residues in vitamin K dependent clotting factors It has a long half life It readily crosses the placenta Liver disease reduces the synthesis of clotting factors thus increases the effect of warfarin