The infant rolls from the tummy to the side at 12 months.
The infant transfers a toy from one hand to the other at age 9 months.
Number 3 is correct.
Rationale: Infants should roll from the tummy to the side by 10 months. By age 15 months, infants should be able to walk alone. Waving good-bye should be accomplished by 7 months. Transferring a toy from one hand to the other occurs by 9 months. New parents should be aware of general time frames for achieving motor skills so that they can notify the health care provider if the infant does not achieve milestones.