Concept:Development follows the cephalocaudal pattern, which means growth and control start from the head and move downward to the toes.
Explanation:A baby first gains control of the head, then the neck, then the arms, then the legs, and finally the feet.
This sequence is called "head to toe" development.
The other options do not describe this well-known pattern. "Complex to simple" is incorrect. "Extremities to centre" describes the opposite proximodistal pattern. "Specific to general" is not a standard principle.
Hence, the correct fill-in is "head" and "toe".
Answer:A. head, toe