According to the Text,what Was One Criticism of Child-Rearing Experts

According to the text,what was one criticism of child-rearing experts during the first half of the 20th century?

A) Their theories were based on observations of white middle-class families.
B) They regarded children as economically worthless but emotionally priceless.
C) Their theories depended too much on tradition and not enough on science.
D) Their theories were based on observation of children with abnormalities.