This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Infectious disease, Subject name: Pediatrics
Which microorganism is responsible for classical presentation of hydrocephalus, chorioretinitis and intracerebral calcification? 
Select and explain. 
A. Toxoplasmosis, B. Rubella, C. Measles, D. CMV
A: Toxoplasmosis
Answer: A: Toxoplasmosis 
Explanation: *Toxoplasmosis is caused by toxoplasma Gondi . * the classical triad of toxoplasmosis is intracranial calcification, hydrocephalus and chorioretinitis. Infants asymptomatic at bih may later present with mental retardation and deafness . *The diagnosis is confirmed by demonstrating a positive toxoplasma IgM antibody in the serum of the affected child. Reference : Ghai essential pediatrics, 9 th edition, pg no:264