<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 45-year-old female who recently immigrated to the United States presents to the community health clinic for episodes of disrupted vision. She is concerned because she knows several people from her hometown who went blind after having these episodes. Over the past several months, she also has developed itchy bumps on her back and lower extremities. Physical exam reveals black hyperpigmented nodules with edema and palpable lymphadenopathy, but is otherwise unremarkable without any visible discharge from the eyes. Her physician explains her underlying disease was likely transmitted by black flies. Which of the following is the most appropriate pharmacotherapy for this patient?? A: Diethylcarbamazine, B: Ivermectin, C: Mebendazole, D: Nifurtimox, E: Praziquantel,  <response>: This is a clinical vignette describing a patient with symptoms of disrupted vision, itchy skin bumps, and swollen lymph nodes. Based on the description of black flies as the likely vector of transmission and the clinical features, this patient likely has onchocerciasis, also known as river blindness. Onchocerciasis is caused by the nematode Onchocerca volvulus which is transmitted by black flies. The drug of choice for treatment is ivermectin, which kills the microfilariae and stops disease progression. Mebendazole treats some nematode infections but not onchocerciasis. Diethylcarbamazine, nifurtimox, and praziquantel are used for other parasitic infections but not optimal for this patient.B: Ivermectin 