One Study Discussed in the Text Demonstrated That Infants with a Particular

Multiple Choice

One study discussed in the text demonstrated that infants with a particular form of one of the genes influencing production of neurotransmitters associated with effortful attention had lower effortful attention than other infants when they also were exposed to poor parenting. What principle is demonstrated by this study?

A) Environment plays a crucial role in the expression of genes.
B) The expression of genes plays a crucial role in one's environment.
C) Some genetic influences operate regardless of environment.
D) Current research methods often do not allow researchers to separate the influences of genetics and environment.