<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A hospitalized 70-year-old woman, who recently underwent orthopedic surgery, develops severe thrombocytopenia of 40,000mm3 during her 7th day of hospitalization. She has no other symptoms and has no relevant medical history. All of the appropriate post-surgery prophylactic measures had been taken. Her labs from the 7th day of hospitalization are shown here:The complete blood count results are as follows:Hemoglobin 13 gdLHematocrit 38Leukocyte count 8,000mm3Neutrophils 54Bands 3Eosinophils 1Basophils 0Lymphocytes 33Monocytes 7Platelet count 40,000mm3The coagulation tests are as follows:Partial thromboplastin time activated 85 secondsProthrombin time 63 secondsReticulocyte count 1.2Thrombin time 2 seconds deviation from controlThe lab results from previous days were within normal limits. What is the most likely cause of the thrombocytopenia?? A: DIC, B: Thrombotic microangiopathy, C: Immune thrombocytopenia, D: Myelodysplasia, E: Heparin-induced thrombocytopenia,  <response>: Based on the information provided, this appears to be a case of isolated thrombocytopenia in an elderly patient who recently underwent orthopedic surgery. The key findings are:- Severe thrombocytopenia of 40,000mm3 on post-op day 7, with prior normal platelet counts- No other hematologic abnormalities - Normal coagulation tests except for mildly prolonged PTT- No clinical bleedingThe differential diagnosis includes:- DIC Disseminated intravascular coagulation - unlikely given normal other cell lines, no schistocytes, and normal coagulation tests except mildly prolonged PTT- TMA Thrombotic microangiopathy - unlikely given no schistocytes and normal other cell lines- ITP Immune thrombocytopenia - possible but less likely in older patient with no prior history- Myelodysplasia - unlikely in normal other cell lines - HIT Heparin-induced thrombocytopenia - most likely given timing and exposure to heparinE: Heparin-induced thrombocytopenia 