The Nurse Is Teaching a New Mother About the Drastic

The nurse is teaching a new mother about the drastic growth and developmental changes her infant will experience in the first year of life. Which of the following describes a developmental milestone occurring in infancy?

A) By 6 months of age the infant's brain weighs half that of the adult brain; at age 12 months, the brain weighs 2.5 times what it did at birth.
B) Most infants triple their birthweight by 4 to 6 months of age and quadruple their birthweight by the time they are 1 year old.
C) The head circumference increases rapidly during the first 6 months: the average increase is about 1 inch per month.
D) The heart triples in size over the first year of life; the average pulse rate decreases from 120 to 140 in the newborn to about 100 in the 1-year-old.