Final answer:
Infants generally begin to say words at about 12 months of age, with 'mama' and 'dada' often being among their first words. They also show understanding of simple commands and demonstrate cognitive milestones like object permanence.(option 2)
Step-by-step explanation:
Infants typically say words beginning at around 12 months of age. Around this time, they may start saying their first words and show that they understand simple commands.
By the end of the first year, babies are usually capable of standing with assistance and may even have taken their first steps.
They also experience cognitive developments, such as understanding that objects continue to exist even when out of sight, also known as object permanence, and can obey simple commands. Infants' early words, often including 'mama' and 'dada', can carry larger meanings beyond mere labeling.