Answer :
Final answer:
The most likely diagnosis for the patient is Protein C deficiency, a genetic disorder that affects the clotting ability of the blood and increases the risk of developing blood clots. Hence option C is correct.
Explanation:
The most likely diagnosis for the patient with a painful rash on her lower extremities is Protein C deficiency. Protein C deficiency is a genetic disorder that affects the clotting ability of the blood. Patients with this condition are at an increased risk of developing blood clots, which can lead to complications such as pulmonary embolism. In this case, the patient's history of pulmonary embolism, along with the presence of necrotic skin lesions and an elevated INR, are consistent with the diagnosis of Protein C deficiency.