Step 1: Child developmentalists divide growth into stages: infancy (birth to 2 years), early childhood (3 to 5 years), late childhood (6 to 11 years) and adolescence, which starts around puberty.
Step 2: Among the given ranges, only 12-15 years falls in the pubertal/teen stage that marks the start of adolescence.
Step 3: So the correct answer is option 1.