Consider the Following Statement, "Babies Who Breastfeed Are Less Likely

Multiple Choice

Consider the following statement, "Babies who breastfeed are less likely to grow into children with behavioral problems by the time they reach age 5 than those who receive formula milk." Which of the following is a plausible confounding variable in this study?

A) Mothers social- economic status
B) The age at which breastfeeding ends
C) The quality of the formula milk
D) All of these
E) None of these