Which Example Would Most Likely Have a Negative Effect on a Child's

Which example would most likely have a negative effect on a child's cognitive and socioemotional skills?

A) Florence loses the ability to speak Polish when her parents begin to speak only English at home.
B) Ji-hu learns to speak three languages by the age of eight.
C) Julieta learns only English even though her parents occasionally speak Spanish to each other.
D) Giuseppe learns to speak English as a second language by the age of seven.