Luis Learned to Raise His Head Off the Floor When

Multiple Choice

Luis learned to raise his head off the floor when he was placed on his stomach. He then learned how to sit unattended and to rock back and forth using his arms and legs before he finally learned how to crawl. This illustrates the principle of __________.

A) cephalocaudal
B) proximodistal
C) hierarchical integration
D) the independence of systems