The main purpose of studying development of children is to know and understand them better. Which of the following are correct in this regard?
1. To know what to expect from child.
2. To known the standards or norms of age groups.
3. To guide the children in different stages.
Select the correct answer

A. 2 and 3

B. 1 and 2

C. 1 and 3

D. All of these

Answer: Option D