<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 31-year-old woman comes to the physician for evaluation of worsening pain, swelling, and erythema in her left leg for the past 4 hours. She returned from a trip to Taiwan to celebrate her sisters wedding 2 days ago. She has no history of serious illness. She is sexually active with one male partner and uses a combined oral contraceptive pill OCP. She does not smoke, drink, or use illicit drugs. Her only other medication is a multivitamin. Her temperature is 37.2C 99F, pulse is 67min, respirations are 16min, and blood pressure is 9060 mm Hg. Examination shows swelling in her left calf and pain behind her left knee when she is asked to dorsiflex her left foot. Laboratory results show elevated D-dimers. Which of the following is the most likely cause of this patients clinical presentation?? A: Increased protein C, B: Decreased fibrinogen, C: ADAMTS13 deficiency, D: Vitamin K supplementation, E: Decreased protein Sn,  <response>: This is a clinical vignette describing a 31-year-old woman with acute onset left leg pain, swelling, and erythema after a recent long plane ride. She has no significant medical history. On exam, she has calf swelling and pain with dorsiflexion concerning for deep vein thrombosis DVT. Her lab work shows elevated D-dimers, which is consistent with thrombosis. The most likely diagnosis given the history, exam, and lab findings is a DVT due to the recent prolonged plane ride. Increased protein C, decreased fibrinogen, and ADAMTS13 deficiency would not explain her presentation. Vitamin K supplementation also does not fit with her acute presentation. Decreased protein S can be associated with increased clotting, but is a chronic condition and would not explain this acute presentation after prolonged immobility.E: Decreased protein S 