Parents Begin to Report That Their Children Start to "Cry

Parents begin to report that their children start to "cry on purpose" within a few months after birth. These reports are:

A) not correct as crying is coordinated by the brain stem until about 1 year of age.
B) correct because crying becomes voluntarily controlled as the cerebral cortex develops within the first few months of life.
C) not correct because the parents are simply hearing a lower pitch in cry due to changes in the vocal tract.
D) correct because after a few months of life, children can coordinate breathing and movements of the vocal tract.