A nurse is assessing a 10-month-old infant. Which of the following findings should the nurse report to the provider?

A. Imitating animal sounds is typically expected by around 12 months, so it is not unusual for a 10-month-old to not yet do this. B. Building a tower of three or four cubes is usually expected around 15-18 months, so it is not concerning at 10 months. C. By 9-10 months, infants are generally able to sit steadily without support. Difficulty in doing so might indicate developmental delay and should be reported. D. Turning pages in a book is a skill typically developed around 12 months, so it is not unusual for a 10-month-old to not yet do this.