<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 55-year-old man comes to the physician because of fatigue and worsening abdominal pain for 4 weeks. He also reports excessive night sweats and a 5.4-kg 12-lb weight loss during this time. He has a neck swelling for 4 days. Physical examination shows a nontender, enlarged, and fixed supraclavicular lymph node. There is splenomegaly. A CT scan of the thorax and abdomen shows massively enlarged axillary, mediastinal, and cervical lymph nodes. Analysis of an excised cervical lymph node shows lymphocytes with a high proliferative index that stain positive for CD20. Which of the following is the most likely diagnosis?? A: Adult T-cell lymphoma, B: Burkitt lymphoma, C: Follicular lymphoma, D: Diffuse large B-cell lymphoma, E: Hodgkin lymphoma,  <response>: Based on the symptoms of fatigue, abdominal pain, night sweats, weight loss, and enlarged lymph nodes, this patient likely has a lymphoma. The positive CD20 stain on the biopsied cervical lymph node indicates a B-cell lymphoma. The enlarged lymph nodes in multiple sites point towards an aggressive, disseminated lymphoma rather than an indolent, localized lymphoma. D: Diffuse large B-cell lymphoma 