This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Impoant Genetic Syndromes, Subject name: Pediatrics
Child with bouts of laughter, what should be the possible diagnosis ? 
Select and explain. 
A. Russel silver syndrome, B. Angelman syndrome, C. Prader willi syndrome, D. Fragile X syndrome
B: Angelman syndrome
Answer: B: Angelman syndrome 
Explanation: ANGELMAN SYNDROM/Happy puppet syndrome Bouts of laughter, intellectual disability, cerebella ataxia and severe developmental delay, Malformations of the skull and facial bones, seizures RUSSELL SILVER SYNDROME - Sho stature , Triangular facies PRADER WILLI SYNDROME - Obesity, Feeding difficulty, Intellectual disabilities FRAGILE X SYNDROME as- XL dominant ,Elongated face, large ears, large testis