<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 33-year-old woman with a history of multiple sclerosis is brought to the physician because of dizziness, urinary incontinence, loss of vision in her right eye, and numbness and weakness of the left leg. She has had recurrent episodes of neurological symptoms despite several changes in her medication regimen. An MRI of the brain shows several new enhancing lesions in the periventricular white matter and the brainstem. Treatment with a drug that binds to CD52 is initiated. Which of the following agents was most likely prescribed?? A: Eculizumab, B: Bevacizumab, C: Alemtuzumab, D: Rituximab, E: Abciximab,  <response>: This is a clinical vignette describing a patient with multiple sclerosis who has new symptoms and MRI findings concerning for a relapse. The history of relapsing-remitting disease course and new enhancing lesions on MRI are typical for multiple sclerosis. The question asks which medication that binds to CD52 was most likely prescribed. CD52 is a protein expressed on lymphocytes, so medications targeting this protein deplete lymphocytes and are used to treat autoimmune diseases like multiple sclerosis. Of the choices provided, alemtuzumab is the only one that binds to CD52. The other options are medications used for other conditions not relevant to this vignette.C: Alemtuzumab 