Answer: This approach enables researchers to track the child's development.
Explanation:
The growth of children varies from one to another. It can be assessed as early as a few months after birth. Typically, infants start crawling around the sixth to seventh month of life, an essential milestone for development. A delay in crawling past seven months is not necessarily alarming but if a child hasn’t started crawling by their first birthday, it is advisable for parents to seek professional guidance.