Which developmental milestone is expected by the end of the first year of life?

By the end of the first year of life, it is typical for infants to achieve the milestone of crawling. Crawling generally occurs between 7 to 10 months, after which many infants begin to explore their environment more actively. This stage is critical for developing motor skills, coordination, and strength.

Walking typically develops around 12 months but is not guaranteed by that age for all infants, as some may walk a little later in their first year. Running and jumping are advanced gross motor skills that usually appear after the first year of life; these skills emerge as children continue to gain strength and balance. Therefore, crawling is the expected milestone for infants by the end of their first year, making it the most appropriate choice.