Answer: a. Fontanel size
Step-by-step explanation:
The fontanel size is useful for determination of age of infant as well as to examine the growth of brain and skull development. Thus this can be used for the physical examination and documentation of the infant.
The posterior fontanelle closes by the age of 1 to 2 months and in some cases it may be remain closed at birth, whereas the anterior fontanelle closes between the age of 9 to 18 months.