<prompt> Which of the following statements about oral anti-coagulants is FALSEThey interfere with an early step in the synthesis of clotting factorsIrrespective of the dose administered, their anticoagulant effect has a latency of onset of 1-3 daysTheir dose is adjusted by repeated measurement of prothrombin timeThey are contraindicated during pregnancy  <response>: Oral anticoagulants inhibit the activation of factor II, VII, IX and X. These do not affect the synthesis of these factors 