This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Genetics And Genetic Disorders, Subject name: Pediatrics
An abnormally tall 11 year old with normal mentation is most likely to have which of the following syndromes? 
Select and explain. 
A. Soto's syndrome, B. Homocystinuria, C. XXY, D. Marfan Syndrome
D: Marfan Syndrome
Answer: D: Marfan Syndrome 
Explanation: Ans. D. Marfan SyndromeMarfan syndrome is an autosomal dominant connective tissue disorder consisting of tall stature, arachnodactyly, thin extremities, increased arm span, and decreased upper body: lower body segment ratio. Additional abnormalities include ocular abnormalities (e.g., lens subluxation), hypotonia, kyphoscoliosis, cardiac valvular deformities, and aortic root dilation.