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
False regarding thumb sucking is: 
Select and explain. 
A. Must be treated vigorously in the first year of life, B. It is a sign of insecurity, C. It is a source of pleasure, D. Can lead to malocclusion
A: Must be treated vigorously in the first year of life
Answer: A: Must be treated vigorously in the first year of life 
Explanation: Ans. A. Must be treated vigorously in the first year of lifeThumb sucking is normal in early infancy. It is a source of pleasure in children and is a sign of insecurity. It can lead to malocclusion of teeth, if it persists beyond 5 years. Best policy is to ignore thumb sucking and concentrate on positive aspects of child's behavior. No treatment is required below 5 year of age.