A Patient, Who First Developed Acute Diarrhea 2 Weeks Ago

A patient, who first developed acute diarrhea 2 weeks ago, presents to clinic reporting profuse watery, bloody diarrheal stools 6 to 8 times daily. The provider notes a toxic appearance with moderate dehydration. Which test is indicated to diagnose this problem?

A) Qualitative and quantitative fecal fat
B) Stool collection for 24-hour stool pH
C) Stool sample for C. difficile toxin
D) Wright stain of stool for white blood cells