Task: Question Answering
Input (English): Question: A 34-year-old woman is admitted to the hospital for pulmonary embolism confirmed by angio-CT. He has no history of recent surgery, trauma or travel. He refers to Raynaud's phenomenon for 2 years, and the previous year he had an abortion at 12 weeks of gestation. He has no family history of venous thromboembolic disease. The activated partial thromboplastin time is 56 sg (normal 25-35 sg) and the platelet count is 120000 / uL. Which of the following diagnostic tests would help you most in the diagnosis? 
 Options:  <1> Antithrombin III. <2> Lupus anticoagulant. <3> Factor V of Leiden. <4> Protein C. <5> Protein S.
Output (English): 2