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: Pediatrics
A 3 year old child is brought to you with history of frequent, violent and rapid swinging movement of the left arm for one week duration. What is the condition described in this scenario called? 
Select and explain. 
A. Chorea, B. Hemiballismus, C. Dystonia, D. Athetosis
B: Hemiballismus
Answer: B: Hemiballismus 
Explanation: The given description is typical of hemiballismus. Chorea is characterised by irregular semi purposive movements like a dance involving the proximal joints. In athetosis there are slow continuous movements mostly at the distal pas of extremities. In dystonia the affected area is maintained in a bizarre position. Ref: Pediatric Clinical Methods by Meharban Singh, 3rd Edition, Page 213