This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cognitive development and defence mechanism, Subject name: Psychiatry
Concrete thinking stage of cognitive development is 
Select and explain. 
A. 0-2 years, B. 2-5 years, C. 5-10 years, D. 10-15 years
C: 5-10 years
Answer: C: 5-10 years 
Explanation: Stages of Intellectual development was postulated by Jean Piaget. 0- 1.5 yrs Senosorimotor 2- 7 yrs Preoperational 7- 11 yrs Concrete operation 11 to end of adolescence Formal operation Concrete operation is so named because in this period child operates and acts on concrete, real and perceivable world of objects and events. Ref: Synopsis of Psychiatry, 11e, pg 94.