This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Growth, Development, and Behavior, Subject name: Pediatrics
Formula to calculate intelligence quotient (IQ): 
Select and explain. 
A. Chronological age/Mental age * 100, B. Mental age - Chronological Age * 100, C. Mental age/Chronological age * 100, D. Mental age + Chronological Age * 100
C: Mental age/Chronological age * 100
Answer: C: Mental age/Chronological age * 100 
Explanation: C i.e. Mental age/Chronological Age * 100Ref: Parks Textbook of Preventive and Social Medicine, 24th editionExplanation:IQ = Mental Age / Chronological Age * 100 Distribution of intelligence in normal populationClassification of TypesI.Q. (Inteligence Quotient)1. Near genius or genius140 and above2. Very superior130-1393. Superior120-1294. Above average110-1195. Normal or average90-1096. Below average80-897. Dull or borderline70-798. Feebleminded, moron50-699. Imbecile25-4910. Idiot0-24