This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Ophthalmology
All of the following statements regarding Sturge weber syndrome are true, EXCEPT: 
Select and explain. 
A. Characterised by nevus flammeus, B. Diffuse choroidal hemangioma may be seen in upto 40% of the cases, C. Up to 85% of individuals may suffer from seizure disorder, D. Mental retardation is seen in only less the 15% of the individuals
D: Mental retardation is seen in only less the 15% of the individuals
Answer: D: Mental retardation is seen in only less the 15% of the individuals 
Explanation: Mental retardation is seen in 60% cases of Sturge weber syndrome. It is an nonfamilial disease characterised by the presence of nevus flammeus on one side of face. 40% of patients with po wine stain develop choroidal hemangioma. They also develop leptomeningeal angiodysplasia of brain and meninges resulting in seizures (85%), mental retardation and cerebral atrophy.