Charity Is Caring for Two Infants in Her Home

Charity is caring for two infants in her home. One is 3 weeks old and the other 5 months old. As Charity sang, she noticed both infants smiling. What likely explains this behavior in both infants?

A) The 3-week-old is likely smiling in response to the sound while the 5-month-old displays a social smile to express happiness toward the familiar caregiver.
B) Both display a developmentally expected social smile in response to the caregiver interaction.
C) Both display a smile that is likely due to high pitched nature of the singing and not the interaction itself.
D) Neither display a social smile as social smiles typically do not appear until after the first year.
E) The 3-week-old responds with a social smile while the 5-month-old imitates the other's. response.