Which of the Following Statements About the Association Between the Learning

Which of the following statements about the association between the learning stimulation of the family environment and children's IQ scores is NOT true?

A) There is a confirmed causal relation between the learning stimulation of the family environment and IQ.
B) IQ is positively correlated with the learning stimulation of the family environment throughout childhood.
C) The learning stimulation of the family environment at an early age is associated with IQ at a later age.
D) If the learning stimulation of the family environment decreases, IQ tends to decrease as well.