This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: parasitology, Subject name: Microbiology
A 33-year-old woman has chronic diarrhea. A fecal sample is obtained. Microscopic identification of which of the following stages of the organism would provide the strongest evidence for cryptosporidiosis 
Select and explain. 
A. Egg, B. Cyst, C. Oocyst, D. Merozoites
C: Oocyst
Answer: C: Oocyst 
Explanation: Oocyst is the correct answer. Egg and cyst stages are not pa of the life cycle of Cryptosporidium. Eggs are produced by helminths, and cyst stages are produced by other intestinal protozoans, such as Entamoeba and Giardia. Merozoites occur within infected epithelial cells but are not the target of diagnostic tests or procedures. Ref:- Baveja textbook of Microbiology