<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 68-year-old man comes to the emergency department 12 hours after the appearance of tender, purple discolorations on his thighs and lower abdomen. He began taking a medication 4 days ago after failed cardioversion for atrial fibrillation, but he cannot remember the name. Physical examination shows a tender bluish-black discoloration on the anterior abdominal wall. A photograph of the right thigh is shown. Which of the following is the most likely explanation for this patients skin findings?? A: Deficiency of vitamin K, B: Decreased synthesis of antithrombin III, C: Antibodies against platelet factor 4, D: Increased levels of protein S, E: Reduced levels of protein C,  <response>: This is a clinical vignette describing a 68-year-old man who developed purple skin discolorations on his thighs and lower abdomen 12 hours ago. He started a new medication 4 days ago after failed cardioversion for atrial fibrillation. The description and photo indicate the patient has ecchymosis bruising. The question asks for the most likely explanation for the ecchymosis in this patient. Based on the history that the skin findings started after beginning a new medication following failed cardioversion for atrial fibrillation, the most likely cause is a medication that increases bleeding risk. Of the choices given, choice E Reduced levels of protein C is the most consistent with an acquired bleeding diathesis and ecchymosis following initiation of anticoagulation.E: Reduced levels of protein C 