Final answer:
Cow's milk should not be given to a 2-month-old formula-fed baby. It is not suitable for infants and their immature digestive systems. Formula milk is designed to provide the necessary nutrients.
Step-by-step explanation:
Cow's milk should not be given to an infant, including a 2-month-old baby. The composition of cow's milk is not suitable for infants, and its proteins are difficult for their immature digestive systems to metabolize and absorb. Additionally, formula milk is specifically designed to provide all the necessary nutrients for a baby's development and growth.