Sruthi studies the association between maternal alcohol use during pregnancy and focused attention in infants. She finds that mothers who drink more alcohol also smoke more cigarettes and have less nutritious diets during pregnancy. All three of these variables are associated with focused attention during infancy. Which of the following is true of this study?
Group of answer choices
Temporal precedence cannot be established between predictor and criterion variables.
She cannot establish covariance in any of her variables.
The autocorrelations suggest that there is a third variable that is unaccounted for.
The study has multiple predictor variables that may explain levels of the criterion variable.