This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Other topics and Adverse effects, Subject name: Pharmacology
[{'content': 'Which of the following statements about oral anticoagulants is FALSE? \nSelect and explain. \nA. They interfere with an early step in the synthesis of clotting factors, B. Irrespective of the dose administered, their anticoagulant effect has a latency of onset of 1-3 days, C. Their dose is adjusted by repeated measurement of prothrombin time, D. They are contraindicated during pregnancy', 'role': 'user'}, {'content': 'Answer: A \nExplanation: (Ref: KDT 6/e p600, 601) Oral anticoagulants inhibit the activation of factor II, VII, IX and X. these do not affect the synthesis of these factors.', 'role': 'assistant'}]