<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:On the 4th day of hospital admission due to pneumonia, a 69-year-old woman develops non-bloody diarrhea and abdominal pain. She is currently treated with ceftriaxone. Despite the resolution of fever after the first 2 days of admission, her temperature is now 38.5C 101.3F. On physical examination, she has mild generalized abdominal tenderness without abdominal guarding or rebound tenderness. Laboratory studies show re-elevation of leukocyte counts. Ceftriaxone is discontinued. Given the most likely diagnosis in this patient, which of the following is the most sensitive test? ? A: Endoscopy , B: Enzyme immunoassay glutamate dehydrogenase , C: Gram stain of stool sample , D: Nucleic acid amplification test, E: Stool culture for bacterial isolation and toxin presence,  <response>: This is a clinical vignette describing a 69-year-old woman who develops diarrhea and abdominal pain while being treated with ceftriaxone for pneumonia. The key findings are:- Diarrhea and abdominal pain on day 4 of hospitalization for pneumonia while on ceftriaxone - Fever resolved initially but now back to 38.5C- Mild abdominal tenderness on exam, no guardingrebound- Re-elevation of leukocyte count- Ceftriaxone discontinuedThe scenario is suggestive of C. difficile infection given the diarrhea and abdominal symptoms in the setting of recent antibiotic use. The question asks for the most sensitive test to confirm the diagnosis.E: Stool culture for bacterial isolation and toxin presence 