Final answer:
Cephalo-caudal is the motor development principle exemplified by a baby learning to sit up before learning to hold a cup upright.
Step-by-step explanation:
The motor development principle exemplified by a baby learning to sit up before learning to hold a cup upright is cephalo-caudal.
This principle states that development typically proceeds from the head down to the feet, meaning that the baby gains control over their upper body and head first before developing control over their lower body.
In this case, the baby needs to develop the muscles and strength in their body to sit up before they can have the coordination and motor skills to hold a cup upright.
Learn more about Motor development